Answer:11
Step-by-step explanation:
Boys : girls=7:1
Sum of ratio=7+1=8
Let them number of girls be y
Then they number of boys=y+66
Total number of pupils=y+y+66
Total number of pupils=2y+66
Number of girls=(girls ratio)/(sum of ratio) x (total number of pupils)
y=1/8 x (2y+66)
Cross multiply
y x 8=2y + 66
8y=2y + 66
Collect like terms
8y-2y=66
6y=66
Divide both sides by 6
6y/6=66/6
y=11
The number of girls is 11
Answer:
Third option. I am sure it!
Step-by-step explanation:
Mark other guy brainliest. He's a great answer and he helped me before
Answer: 9
Step-by-step explanation:
A=(a+b)/2 *h
135= 30/2* h
135= 15 * h
135/15= h
9=h
Answer:
8
Step-by-step explanation:
add 4 plus 4 then omg watch this you get 8 abracadabra....
you're welcome
