Answer:
18/48 = 30/50 is false
Step-by-step explanation:
20/50 and 40/100 both equal 0.4
12/15 and 20/25 both equal 0.8
etc.
It need a lone number. so something like x2+x+3
45 min. - 4 peoples - 5 walls
? min. - 6 peoples - 4 walls
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180 min. - 1 man - 5 walls ⇒
36 min. - 1 man - 1 wall ⇒
6 min. - 6 peoples - 1 wall ⇒
24 min. - 6 peoples - 4 walls (answer)
First we want to find how much it costs for 1 stamp, so we do 8.28 divided by 18, which equals 0.46. Then, we multiply 0.46 and 12, which is 5.52. Therefore, it would cost $5.52 to buy 12 stamps.