Question

A man increases his speed by 40% and reaches his office from his house 12 minutes early
Find the time taken by him to reach his office travelling at his usual speed?
1) 42 minutes
2) 84 minutes 3) 30 minutes 4) 60 minutes​

Answer 1

Step-by-step explanation:

let the original speed of person be s and time taken be t for distance D.

D= s*t ---------------(1)

when we increase his speed by 40 % then his speed is 1.4s and time is (t-12) minutes .

so D=1.4s*(t-12) -----------------(2)

on dividing these equations, we get

1 = 1.4(t-12)/t

t= 1.4t - 16.8

0.4t = 16.8

t = 42 minutes (1) (ans.) ✍️

[ mark as brainlist if you understand my solution ]