Question

A student divided a number by 7/2 instead of 2/7. Calculate the percentage error.

• A. 88.25%
• B. 91.8%
• C. 81.9%
• D. 92%

Answer 1

Answer:

B. 91.8%

Let the number be 'X'. The student divides the number by 7/2. Thus, error value = X//(7/2) = 2X/7 But it should be divided by 2/7. Thus, true value = X/(2/7) = 7X/2 Difference in the two values = (7X/2) - (2X/7) = 45X/14 Required % error = (difference in two values/true value) × 100 = [(45x/14)/(7x/2)] × 100 = 91.8%