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: 5.2
Step-by-step explanation:
3*7 = 21
21/5 = 4.2
Answer:
Step-by-step explanation:
=5
$30 • 10%
10% = 0.10
30 • 0.10 = 3
The answer is $27. They got $3 off.
$30 - $3 = $27.
