SOLUTION: A collection of 15 coins is worth $1.00. If the coins are dimes and nickels, how many of each coin are there? I have only been taught to do it when you are told that one of th

Method 1: Solving for 2 unknowns

Let number of dimes and number of nickels, be D and N, respectively. Then we have:

   D +     N = 15 --------- Denomination-number equation

.1D + .05N =  1 --------- Denomination-value equation

Solve for D or N and substitute solved variable into either equation to determine value of other variable



Method 2: Solving for 1 unknown

Let number of dimes, be D

Then number of nickels = 15 - D. We now have:

.1D + .05(15 - D) = 1 -------- Value equation

Solve for D, and then SUBTRACT that value from 15 (total number of coins) to determine number of nickels



Then do a check!! 

===================

If you need a complete and detailed solution, let me know!!

Send comments, “thank-yous,” and inquiries to “D” at MathMadEzy@aol.com.

Further help is available, online or in-person, for a fee, obviously. 



For FREE info and answers to questions about the ASVAB exam, the NYS 3 – 8 city/state wide exams,GENERAL

MATH and HOMEWORK QUESTIONS, or MATH QUESTIONS related to the Regents Integrated Algebra, 

Regents Geometry, Regents Algebra 2/Trigonometry, SHSAT, COOP/HSPT/TACHS, PSAT, SAT, ACT, SSAT/ISEE,

GRE, CLEP, and the TASC/GED, you can visit: http://asvabstudyzone.freeforums.net/.