Answer:
There are 8 boys.
Step-by-step explanation:
2/5 = x/20
Set it up as a proportion.
2*20=5x
Cross Multiply
40=5×
40/5=x
8=x
Solve for x
Since it's 0.6 kg for 5 gallons, we'd want to find the unit rate aka the amount of kg's per gallon. To find that, we have to see how many times 5 goes into 0.6, which is 0.6/5=0.12 for 1 gallon. Multiply that by 7 to get 0.84 for 7 gallons!