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15a + 6b = 30, what is the value of a-b?
1. b = 5 – 2.5a
2. 9b = 9a – 81
1. b = 5 – 2.5a
2. 9b = 9a – 81
- a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;
- b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;
- c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;
- d)EACH statement ALONE is sufficient to answer the question asked;
- e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.
Correct answer is option 'B'. Can you explain this answer?
Verified Answer
15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9...
Be aware that simply because you have two equations with two unknowns does not mean that a solution exists. You must have two unique equations with two unknowns in order for a solution to exist.
Evaluate Statement (1) alone.
There are two possible ways to solve this problem:
Method (1): Substitute b from Statement (1) into the original equation.
15a + 6(5 – 2.5a) = 30
15a + 30 - 15a = 30
30 = 30
0 = 0
Based upon this answer, the equation in Statement (1) is the equation in the original question solved for b. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Evaluate Statement (1) alone.
There are two possible ways to solve this problem:
Method (1): Substitute b from Statement (1) into the original equation.
15a + 6(5 – 2.5a) = 30
15a + 30 - 15a = 30
30 = 30
0 = 0
Based upon this answer, the equation in Statement (1) is the equation in the original question solved for b. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Method (2): Rearrange the equation in Statement (1) and subtract this equation from the original equation.
b = 5 – 2.5a
b + 2.5a = 5
2.5a + b = 5
Multiply by 6 so b's cancel:15a + 6b = 30
This method also shows that the equation in Statement (1) is nothing more than the original equation rearranged. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Statement (1) is NOT SUFFICIENT.
Evaluate Statement (2) alone.
Try to line up the two equations so that you can subtract them:
9b = 9a – 81
81 + 9b = 9a
81 = 9a - 9b
Statement (2) Equation: 9a - 9b = 81
Original Question Equation: 15a + 6b = 30
At this point, you can stop since you know that you have two unique equations and two unknowns. Consequently, there will be a solution for a and for b, which means there will be one unique value for a-b. Statement (2) is SUFFICIENT.
If you want to solve to see this (Note: Do not solve this in a test as it takes too much time and is not necessary):
Multiply (2) by 4: 36a - 36b = 324
Multiply Original by 6: 90a + 36b = 180
b = 5 – 2.5a
b + 2.5a = 5
2.5a + b = 5
Multiply by 6 so b's cancel:15a + 6b = 30
This method also shows that the equation in Statement (1) is nothing more than the original equation rearranged. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Statement (1) is NOT SUFFICIENT.
Evaluate Statement (2) alone.
Try to line up the two equations so that you can subtract them:
9b = 9a – 81
81 + 9b = 9a
81 = 9a - 9b
Statement (2) Equation: 9a - 9b = 81
Original Question Equation: 15a + 6b = 30
At this point, you can stop since you know that you have two unique equations and two unknowns. Consequently, there will be a solution for a and for b, which means there will be one unique value for a-b. Statement (2) is SUFFICIENT.
If you want to solve to see this (Note: Do not solve this in a test as it takes too much time and is not necessary):
Multiply (2) by 4: 36a - 36b = 324
Multiply Original by 6: 90a + 36b = 180
6*Original + 2*Statement(2): (90a + 36a) + (36b + -36b) = 180 + 324
126a = 204
a = 4
126a = 204
a = 4
Solve for b:
9b = 9(4) - 81 = -45
b = -5
9b = 9(4) - 81 = -45
b = -5
a - b = 4 - (-5) = 4 + 5 = 9
Since Statement (1) alone is NOT SUFFICIENT and Statement (2) alone is SUFFICIENT, answer B is correct.
Since Statement (1) alone is NOT SUFFICIENT and Statement (2) alone is SUFFICIENT, answer B is correct.
Most Upvoted Answer
15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9...
Be aware that simply because you have two equations with two unknowns does not mean that a solution exists. You must have two unique equations with two unknowns in order for a solution to exist.
Evaluate Statement (1) alone.
There are two possible ways to solve this problem:
Method (1): Substitute b from Statement (1) into the original equation.
15a + 6(5 – 2.5a) = 30
15a + 30 - 15a = 30
30 = 30
0 = 0
Based upon this answer, the equation in Statement (1) is the equation in the original question solved for b. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Evaluate Statement (1) alone.
There are two possible ways to solve this problem:
Method (1): Substitute b from Statement (1) into the original equation.
15a + 6(5 – 2.5a) = 30
15a + 30 - 15a = 30
30 = 30
0 = 0
Based upon this answer, the equation in Statement (1) is the equation in the original question solved for b. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Method (2): Rearrange the equation in Statement (1) and subtract this equation from the original equation.
b = 5 – 2.5a
b + 2.5a = 5
2.5a + b = 5
Multiply by 6 so b's cancel:15a + 6b = 30
This method also shows that the equation in Statement (1) is nothing more than the original equation rearranged. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Statement (1) is NOT SUFFICIENT.
Evaluate Statement (2) alone.
Try to line up the two equations so that you can subtract them:
9b = 9a – 81
81 + 9b = 9a
81 = 9a - 9b
Statement (2) Equation: 9a - 9b = 81
Original Question Equation: 15a + 6b = 30
At this point, you can stop since you know that you have two unique equations and two unknowns. Consequently, there will be a solution for a and for b, which means there will be one unique value for a-b. Statement (2) is SUFFICIENT.
If you want to solve to see this (Note: Do not solve this in a test as it takes too much time and is not necessary):
Multiply (2) by 4: 36a - 36b = 324
Multiply Original by 6: 90a + 36b = 180
b = 5 – 2.5a
b + 2.5a = 5
2.5a + b = 5
Multiply by 6 so b's cancel:15a + 6b = 30
This method also shows that the equation in Statement (1) is nothing more than the original equation rearranged. Consequently, we only have one equation and two unknowns. There is not enough information to determine a-b.
Statement (1) is NOT SUFFICIENT.
Evaluate Statement (2) alone.
Try to line up the two equations so that you can subtract them:
9b = 9a – 81
81 + 9b = 9a
81 = 9a - 9b
Statement (2) Equation: 9a - 9b = 81
Original Question Equation: 15a + 6b = 30
At this point, you can stop since you know that you have two unique equations and two unknowns. Consequently, there will be a solution for a and for b, which means there will be one unique value for a-b. Statement (2) is SUFFICIENT.
If you want to solve to see this (Note: Do not solve this in a test as it takes too much time and is not necessary):
Multiply (2) by 4: 36a - 36b = 324
Multiply Original by 6: 90a + 36b = 180
6*Original + 2*Statement(2): (90a + 36a) + (36b + -36b) = 180 + 324
126a = 204
a = 4
126a = 204
a = 4
Solve for b:
9b = 9(4) - 81 = -45
b = -5
9b = 9(4) - 81 = -45
b = -5
a - b = 4 - (-5) = 4 + 5 = 9
Since Statement (1) alone is NOT SUFFICIENT and Statement (2) alone is SUFFICIENT, answer B is correct.
Since Statement (1) alone is NOT SUFFICIENT and Statement (2) alone is SUFFICIENT, answer B is correct.
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15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer?
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15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? for GMAT 2025 is part of GMAT preparation. The Question and answers have been prepared according to the GMAT exam syllabus. Information about 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for GMAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer?.
15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? for GMAT 2025 is part of GMAT preparation. The Question and answers have been prepared according to the GMAT exam syllabus. Information about 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for GMAT 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer?.
Solutions for 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for GMAT.
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Here you can find the meaning of 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer?, a detailed solution for 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? has been provided alongside types of 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice 15a + 6b = 30, what is the value of a-b?1. b = 5 – 2.5a2. 9b = 9a – 81a)Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer thequestion asked;b)Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer thequestion asked;c)BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked,but NEITHER statement ALONE is sufficient;d)EACH statement ALONE is sufficient to answer the question asked;e)Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked,and additional data are needed.Correct answer is option 'B'. Can you explain this answer? tests, examples and also practice GMAT tests.
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