Answer:
m= -5/6
Step-by-step explanation:
So the ratio of boys to girls is 12:24.. now, is that an equivalent ratio as 2 boys for 4 girls? or 2:4? let's see.

you could start simplifying the 12/24 fraction by dividing by some common multiple, say 2, and get 6/12, then divide by 3 and get 2/4 and stop there.
then you'll notice that 12/24 is really 2/4 in disguise.
Answer:
55 inches
Step-by-step explanation:
2 posters x 28 inches each = 56
221 - 56 = 165 inches
3 blank spaces on wall
165 ÷ 3 = 55 inches between posters and on either side