An employee may claim ₹ 7 for each km when he travels by taxi and ₹ 6 for each km if he drives his own car. If in one week he claimed ₹ 675 for travelling 90 km, how many kms did he travel by taxi?
(a)135
(b)155
(c)162
(d)170
Answer
Answer (as printed): A
Explanation
Let the distance travelled by taxi be $x \mathrm{km}$. Then, distance travelled by own car $=(90-x) \mathrm{km}$. $$\therefore \quad 7 x+6(90-x)=675 \Leftrightarrow x=675-540=135 \mathrm{km} .$$