Question

A student multiplied a number by 5/11 instead 11/5 what is the percentage error
Option
A.51%
B.42 %
C.79.34%
D.71.5%​

Answer 1

Answer:

79.34 this will be my answer.

Answer 2

Percentage

(c) 79.34%

Let the number be x.

When multiplied by 5/11 it will become 5x/11, it is what it was incorrectly written.

When multiplied by 11/5 it will become 11x/5, it is what it should actually be.

The error will be, (actual-wrong) i.e.

$\frac{11x}{5}- \frac{5x}{11}=\frac{121x-25x}{55} =\frac{96x}{55}$

Percentage error will be,

$\frac{(\frac{96x}{55}) }{(\frac{11x}{5}) }\times 100=\frac{96x}{55}\times\frac{5}{11x}\times100=79.338$

Hence, the percentage error will be 79.34%.

Note: In these type of question the actual value needs to be in mind, otherwise question will be entirely wrong.