Answer :
Ratio of crushed gravel to water to cement mix = 8:7:5 (for a total of 20 parts)
Thus . .
8/20 = fraction of crushed gravel
7/20 = fraction of water
5/20 = fraction of cement mix
If total is 200 kg, then . . .
(8/20)*(200 kg) = 80 kg crushed gravel
(7/20)*(200 kg) = 70 kg water
(5/20)*(200 kg) = 50 kg cement mix
Thus . .
8/20 = fraction of crushed gravel
7/20 = fraction of water
5/20 = fraction of cement mix
If total is 200 kg, then . . .
(8/20)*(200 kg) = 80 kg crushed gravel
(7/20)*(200 kg) = 70 kg water
(5/20)*(200 kg) = 50 kg cement mix