At the beginning of the school year dance, the ratio of the number of boys to the number of girls was 3: 7 , if there were 100 more girls than boys, how many boys were at the dance? …. how many girls were at the dance?

boys (b): b

girls (g): b + 100

total (T) = b + g

I am going to set up the proportion as "boys" to "total"

⇒

⇒ 3(2b + 100) = 10(b)

⇒ 6b + 300 = 10b

⇒          300 = 4b

⇒            75 = b

girls (g): b + 100   = (75) + 100   = 175

boys = 75, girls = 175

the forst and 3rd

step-by-step explanation:

hello from mrbilldoesmath!

answer:

the domain is the set { -2, 0, 2, 3}

discussion:

the domain is the set of x values in the ordered pairs (x,y). taking the x, or first component, of each ordered pair gives   -2, 0, 2, 3.

you,

mrb