It is number 3. Have a good day.
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:
(-3,-8)
Step-by-step explanation:
okay so what we can do here is elimination
we can do this first by multiplying the entire second equation by 2
so then it would become
2(5x-2y=1)
10x-4y=2
now we can add the two equations together which will eliminate y
so
-8x+4y=-8 plus
10x-4y=2 equals
2x=-6
we did that by combining like terms
next we can simplify that
x=-3
now we can plug that into the equation
-8(-3)+4y=-8
simplify
24+4y=-8
4y=-32
y=-8
our answer would be
(-3,-8)
Answer: 113.1 i think sorry im bad at pi U_U
Step-by-step explanation: