Answer:
Step-by-step explanation:
4 doz for 7.25 = 12 doz for x
set up a proportion
4 12
------ = ------- cross multiply
7.25 x
4x = (7.25)(12)
4x = 87
x = 87/4
x = 21.75 <====
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so we have 0.49 for the first oz.....and 0.22 for each additional oz....and there is 4 additional oz's because 5 - 1 = 4....so thats 0.49 + 4(0.22) = 0.49 + 0.88 = $ 1.37 for the cost of a 5 oz letter. <===