Question 1002345
Over the last three evenings, Heather received a total of 
109
phone calls at the call center. The third evening, she received 
4
times as many calls as the second evening. The first evening, she received 
7
more calls than the second evening. How many phone calls did she receive each evening? 
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Let the # of calls per evening be a,b,c::
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Equations:
a + b + c = 109
c = 4b
a = b + 7
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Substitute for a and c and solve for "b":
b+7 + b + 4b = 109
6b = 102
b = 17 (# of calls on the 2nd evening)
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a = b+7 = 24 (# of calls on the 1st evening)
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c = 4b = 4*17 = 68 (# of calls on the 3rd evening)
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Cheers,
Stan H.
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