5 elephants
Step-by-step explanation:
Ratio of elephants to hippo = 1:2
It means for each elephant , we have 2 hippos
when the number of hippos = 10
let the number of elephants = y
1 elephant = 2 hippos
y = 10 hippos
cross multiply:
1(10) = 2(y)
10 = 2y
divide both sides by 2:
10/2 = 2y/2
5 = y
Hence, when there are 10 hippos, we would have 5 elephants