In a class of 40 students, the number of students who study French is 10 more than the number who study History.How many study History, French, only one subject?
The number of students who study history is 10 more than those who study French means:
H = F + 10
Replace thin in equation:
F + H = 32
F + F + 10 = 32
2 F + 10 = 32
2 F = 32 - 10 = 22
F = 22 / 2
F = 11
H = F + 10
H = 11 + 10 = 21
11 students study French
21 students study History
8 students study both subject