Question

On a market day Mrs.lana walks to the market from her home at steady speed. This journey normally takes her 2 hours to complete.
She finds, however that by increasing her speed in km/hr.she can save 20 minutes. Find her usual speed in km/hr?

Answer 1

d = r1*t,
d = r1 * 2
r1 = d/2 = Her usual speed

d = r2 * (2-1/3) = r * (6/3-1/3) = r2 * 5/3,
r2 = 3d/5.
r2/r1 = (3d/5)/(d/2) = 3d/5 * 2/d = 6/5.
r1 = 5r2/6.

I need to know her 2nd rate(r2).