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The arithmetic mean between a and 10 is 30, the value of ‘a’ should be
- a)45
- b)60
- c)50
- d)53
Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
The arithmetic mean between a and 10 is 30, the value of ‘a&rsqu...
A is -10.
To solve for a, we can use the formula for the arithmetic mean:
mean = (a + 10) / 2
We know that the mean is 30, so we can substitute:
30 = (a + 10) / 2
Multiplying both sides by 2, we get:
60 = a + 10
Subtracting 10 from both sides, we get:
50 = a
Therefore, the value of a is 50.
However, this answer doesn't make sense because if the arithmetic mean between a and 10 is 30, then a must be less than 30. In fact, we can check that if a is 50, then the mean would be (50 + 10) / 2 = 30, which is correct.
So we made a mistake somewhere. Let's try again:
mean = (a + 10) / 2
30 = (a + 10) / 2
Multiplying both sides by 2, we get:
60 = a + 10
Subtracting 10 from both sides, we get:
50 = a - this is incorrect!
We made a mistake in the last step. We should have subtracted 10 from both sides first, then multiplied by 2:
30 = (a + 10) / 2
60 = a + 10
50 = a
Therefore, the value of a is -10.
To solve for a, we can use the formula for the arithmetic mean:
mean = (a + 10) / 2
We know that the mean is 30, so we can substitute:
30 = (a + 10) / 2
Multiplying both sides by 2, we get:
60 = a + 10
Subtracting 10 from both sides, we get:
50 = a
Therefore, the value of a is 50.
However, this answer doesn't make sense because if the arithmetic mean between a and 10 is 30, then a must be less than 30. In fact, we can check that if a is 50, then the mean would be (50 + 10) / 2 = 30, which is correct.
So we made a mistake somewhere. Let's try again:
mean = (a + 10) / 2
30 = (a + 10) / 2
Multiplying both sides by 2, we get:
60 = a + 10
Subtracting 10 from both sides, we get:
50 = a - this is incorrect!
We made a mistake in the last step. We should have subtracted 10 from both sides first, then multiplied by 2:
30 = (a + 10) / 2
60 = a + 10
50 = a
Therefore, the value of a is -10.
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Community Answer
The arithmetic mean between a and 10 is 30, the value of ‘a&rsqu...
A is -10.
To find the arithmetic mean between two numbers, we add them together and divide by 2. So we can set up the equation:
(a + 10) / 2 = 30
Multiplying both sides by 2, we get:
a + 10 = 60
Subtracting 10 from both sides, we get:
a = 50
However, this answer doesn't make sense because the problem states that the arithmetic mean is between a and 10, and 50 is greater than 10. So we made an error somewhere.
Let's try setting up the equation with a as the unknown:
(a + 10) / 2 = 30
Multiplying both sides by 2, we get:
a + 10 = 60
Subtracting 10 from both sides, we get:
a = 50
Wait a minute, this is the same answer we got before. But why does it work now?
The reason is that we made an assumption in our first attempt to solve the problem, namely that a is greater than 10. But this assumption is not necessarily true. In fact, if a is less than -10, then the arithmetic mean between a and 10 will be less than 10, which is not consistent with the given information that the mean is 30.
So we need to consider the possibility that a is negative. Let's try again:
(a + 10) / 2 = 30
Multiplying both sides by 2, we get:
a + 10 = 60
Subtracting 10 from both sides, we get:
a = 50
Wait a minute, this is still the same answer we got before. Did we make another mistake?
Actually, no. This time, the answer makes sense. If a is 50, then the arithmetic mean between a and 10 is:
(50 + 10) / 2 = 30
which is what we were given.
But why does this answer work when our first attempt at solving the problem led us astray?
The reason is that we made an unwarranted assumption in our first attempt, namely that a is greater than 10. In reality, a could be any number less than 30 (since the mean is 30 and 10 is the upper limit). So we need to consider all possible values of a that satisfy the given information, and then choose the one that makes the most sense in context.
In this case, the only value of a that works is -10, because it is the only value less than 30 that results in a mean of 30.
So the final answer is:
If the arithmetic mean between a and 10 is 30, then the value of a is -10.
To find the arithmetic mean between two numbers, we add them together and divide by 2. So we can set up the equation:
(a + 10) / 2 = 30
Multiplying both sides by 2, we get:
a + 10 = 60
Subtracting 10 from both sides, we get:
a = 50
However, this answer doesn't make sense because the problem states that the arithmetic mean is between a and 10, and 50 is greater than 10. So we made an error somewhere.
Let's try setting up the equation with a as the unknown:
(a + 10) / 2 = 30
Multiplying both sides by 2, we get:
a + 10 = 60
Subtracting 10 from both sides, we get:
a = 50
Wait a minute, this is the same answer we got before. But why does it work now?
The reason is that we made an assumption in our first attempt to solve the problem, namely that a is greater than 10. But this assumption is not necessarily true. In fact, if a is less than -10, then the arithmetic mean between a and 10 will be less than 10, which is not consistent with the given information that the mean is 30.
So we need to consider the possibility that a is negative. Let's try again:
(a + 10) / 2 = 30
Multiplying both sides by 2, we get:
a + 10 = 60
Subtracting 10 from both sides, we get:
a = 50
Wait a minute, this is still the same answer we got before. Did we make another mistake?
Actually, no. This time, the answer makes sense. If a is 50, then the arithmetic mean between a and 10 is:
(50 + 10) / 2 = 30
which is what we were given.
But why does this answer work when our first attempt at solving the problem led us astray?
The reason is that we made an unwarranted assumption in our first attempt, namely that a is greater than 10. In reality, a could be any number less than 30 (since the mean is 30 and 10 is the upper limit). So we need to consider all possible values of a that satisfy the given information, and then choose the one that makes the most sense in context.
In this case, the only value of a that works is -10, because it is the only value less than 30 that results in a mean of 30.
So the final answer is:
If the arithmetic mean between a and 10 is 30, then the value of a is -10.
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The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer?
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The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer? for CA Foundation 2025 is part of CA Foundation preparation. The Question and answers have been prepared according to the CA Foundation exam syllabus. Information about The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for CA Foundation 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer?.
The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer? for CA Foundation 2025 is part of CA Foundation preparation. The Question and answers have been prepared according to the CA Foundation exam syllabus. Information about The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for CA Foundation 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The arithmetic mean between a and 10 is 30, the value of ‘a’ should bea)45b)60c)50d)53Correct answer is option 'C'. Can you explain this answer?.
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