In a group of three numbers first is double of second and half of thir...
GIVEN:
First number = 2 × Second Number
First Number = 1/2 × Third number
Average of three numbers = 56
FORMULA USED:
Average = First number + Second number + Third number / 3
CALCULATION:
Let the first number be ‘x’
Second number = x/2
Third number = 2x
According to the question,
(x + x/2 + 2x)/3 = 56
(2x + x + 4x)/6 = 56
7x = 56 × 6
x = 48
∴ Required difference = 96 - 48 = 48
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In a group of three numbers first is double of second and half of thir...
To solve this problem, let's assume the three numbers as follows:
First number = x
Second number = y
Third number = z
According to the given conditions:
- The first number is double the second number: x = 2y
- The first number is also half the third number: x = z/2
- The average of the three numbers is 56: (x + y + z)/3 = 56
Now, let's solve these equations step by step to find the values of x, y, and z.
Solving for x in terms of y using the equation x = 2y:
- Substitute the value of x in the third equation: 2y = z/2
- Multiply both sides of the equation by 2 to eliminate the fraction: 4y = z
Substituting the value of x in the second equation:
- Substitute the value of x in the second equation: 2y = z/2
- Multiply both sides of the equation by 2 to eliminate the fraction: 4y = z
Now, let's substitute these values in the average equation:
- Substitute the value of x = 2y and z = 4y in the average equation: (2y + y + 4y)/3 = 56
- Simplify the equation: (7y)/3 = 56
- Multiply both sides of the equation by 3 to isolate y: 7y = 168
- Divide both sides of the equation by 7 to solve for y: y = 24
Now that we have the value of y, we can substitute it back into the equations to find the values of x and z.
Substituting y = 24 in the equation x = 2y:
- x = 2(24)
- x = 48
Substituting y = 24 in the equation z = 4y:
- z = 4(24)
- z = 96
Therefore, the first number is 48 and the third number is 96. The difference between the first number and the third number is 96 - 48 = 48.
Hence, the correct answer is option B) 48.