Aman jogs to the shop and back in half an hour on the way he jogs at 4m/s and on the way back he jogs at 5m/s ignoring time spent in the shop find the distance to the shop

Ratio 4:5
There are 9 total.
30 mins = 1800 secs. 
1800 divided by 9 = 200
200 secs = 3mins 20secs
200 is one "part" of the ratio, so multiply it by 4, then 5
800:1000
                           This is the important one
                                           V
13mins, 20secs: 16mins 40secs
Distance is speed x time,
16mins x 4 = 64
40 secs = 2/3
 x 4 = 1.6666
Distance to shop - 65.6m