Here the two samples should be comparable .
The total number of cows in the farm = 200
the total number of cows giving milk = 150
the total number of cows in corral = 20
Suppose total number of cows giving milk in corral = x
The ratio of the total number of cows present to the total number of cows giving milk should be same in farm and corral
so : 200 = 20
------- -------
150 x
now we do cross multiplication :
200 x = 150* 20
200x = 3000
x= 3000/200
x= 15
SO we expect 15 cows in corral should be giving milk .
Answer : 15
ABC and CBH are right angles
DBC = 90 - 37 = 53
CBJ = 90 - 31 = 59
HBD = 180 - 37 = 143
or
HBD = 31 + 53 + 59 = 143 :)
Prime only has two factors one and its self a composite number has more factor than one and its self
exsample: 12 - 1,2,3,4,6,12 = 12 is a composite number
7 - 1,7 =prime number