Answer:
250 minutes with the flat rate of $29.
x would be the number of minutes called.

Tracy would be charged by $0.35 per minute.


It would last 13.5 weeks because you would make a proportion:
12/16 = x/18 and then cross multiply. You would get 216=16x, then you have to divide both sides by 16 to get x = 13.5
K:A
5:3 (before)
15:9
since the total number of stamps didn't change, the total ratio should be the same.
7:5(after)
14:10
so this means 1 unit is 10stamps.
14-10=4
4 X 10= 40
Kaye have 40 more stamps than Alberto.