Question 821492
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(x + y)/21 = 171
(1/21)x + (1/21)y = 171
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x/20 = 170
(1/20)x = 170
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(1/21)x + (1/21)y = 171
(1/20)x = 170
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(0.047619)x + (0.047619)y = 171
(0.05)x = 170
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0.047619x + 0.047619y = 171
0.05x = 170
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x= 3400
y= 191.003591
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x= 3400/20/12 = average age of the younger students = 14.2 years
y= 191.003591/12 = age of the oldest student = 15.916966 years
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answer:
age of the oldest student = 15.9 years = 15 years and 11 months
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