Question

A motor starts with the speed of 70 km/h with its speed increasing every two hours by 10 km/h.In how many hrs will it cover 480 km/s.

Answer 1

10KM/2 HOUR = 5 KM/ HOUR
WELL THIS IS IN AP
WHERE
D = 5 KM/ H
A = 70 KM/H
tn = 480 km/h

tn = a + (n-1)d
480 = 70 + (n-1) 5
410 = (n-1) 5
( n - 1) = 410/5 = 82
n = 82+1 = 83

in 83 hours