Question

The number of boys in ninth grade is 12 less than than twice the number of girls. There are 51 students in ninth grade. How many are girls?

Answer 1

n=12-g
n+g=51

Answer 2

let n represent boys
let g represent girls

Answer 3

G = 21

Answer 4

B + G = 51 , and
B = 2G - 12

Now, replace the B in the first equation with its value from the second equation
(2G - 12) + G = 51

Remove the brackets
2G - 12 + G = 51

Add 12 to both sides
2G + G = 51 + 12
3G = 63

Divide both sides by 3
G = 21

Now, to check if we're right,
Replace G in the first equation
B + 21 = 51
B = 30

If that's right then
30 = 2(21) - 12
30 = 42 - 12

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Answer 5

oh nvm n=12-2g

Answer 6

So the answer to how many girls there are the answer is 21

Answer 7

yes 21