Question 892870
How many pictures must be sent for both plans to cost the same and how much will the cost be? C is the total cost and P is the number of pictures.
 Data Plan A: C=.3p + 45 
Data Plan B: C=.2p + 60 
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Using substitution::
Since both expressions describe "C", we can substitute to get:
0.3p+45 = 0.2p + 60
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Solve for "p"::
0.1p = 15
p = 150 (# of pictures to make Plan A cost equal Plan B cost)
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Cheers,
Stan H.
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