Question 1127683
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Sandra has a total of one hundred fifty-one pennies, nickels and quarters. She has a total of $10.15. 
She has one more quarter than nickels and three times as many pennies as nickels. How many of each coin does she have?


amchaconz@allumni.stanford.edu
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            It is clear, from the first glance, that the problem is over-defined: it contains more data than it is required for the solution.


            So, let be careful and will see what will happen in the course of the solution.


 
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Let N be the number of nickels.


Then the number of quarters is (N+1)  and the number of pennies is 3N.


Your "coin" equation is  

    N + (N+1) + 3N = 151.


    5N + 1 = 151

    5N = 151-1 = 150  ====>  N = 150/5 = 30.


So far, we got  30 nickels, 31 quarter and 3*30 = 90 pennies.


<U>CHECK</U>.   30*5 + 31*25 + 90 = 10.15 cents.    !  Correct !


         The input data is consistent; the solution is correct.


<U>Answer</U>.  30 nickels, 31 quarter and 90 pennies.
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