Cost of month plan = $40
Cost of minutes used = $0.45 after 700 minutes
Total cost = $48.10
Let x be the total minutes used
Total cost = 40 + 0.45(x - 700)
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Form the equation and solve x
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40 + 0.45(x - 700) = 48.10
40 + 0.45x - 315 = 48.10
0.45x - 275 = 48.10
0.45x = 48.10 + 275
0.45x = 323.10
x = 323.10 ÷ 0.45
x = 718
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Answer: John had used 718 mins this month
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6 2/5 is the answer, because 15 1/2 divided by 2 2/5 is 6 2/5
Male student: 40/100 = 2/5
graduate: 520/2106 = 65/252
2/5 + 65/252
= 829/1260 ( this is the probability)
