You do inverse op
2.7+23.5=26.2
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:
closest answer = 81
Step-by-step explanation:
81/27 = 3
81/30= 2.7
81/45 = 1.8
Answer:
x = 11
y = 17
Step-by-step explanation:
We know that opposite angles (or vertical angles) are equal.
So
8x + 7 = 9x - 4
Subtract 8x from both sides of the equation
8x - 8x + 7 = 9x - 8x - 4
7 = x - 4
Add 4 to both sides of the equation
7 + 4 = x - 4 + 4
11 = x
Looking at the other 2 angles,
5y = 7y - 34
Subtract 7 y from both sides of the equation
5y - 7y = 7y - 7y - 34
-2y = -34
Divide both sides by -2
-2y/-2 = -34/-2
y = 17