Question

Rohit travel from P to Q with uniform velocity of 40 km per hour and returns balk with a speed of 30 km per hour at the same path find the average speed of rohit

Answer 1

SOLUTION

AVERAGE SPEED = TOTAL DISTANCE/ TOTAL TIME TAKEN

Let P to Q distance Be = x

Then TOTAL DISTANCE = 2x

TIME = DISTANCE / SPEED

Time (P to Q) = x/40

Time (Q to P) = x/30

TOTAL TIME = x/40 + x/30

= 70x/1200

= 7x/120

AVERAGE SPEED = TOTAL DISTANCE/ TOTAL TIME TAKEN

= 2x /(7x/120)

= 2x × 120/7x

= 240/7

= 34.2857142857 (Approx)