Answer:
D=15 so N=10
Step-by-step explanation:
N+D=25 where the coins make up the number of nickels, N and the number of dimes, N
Now each nickel is worth .05 (not .5)
Each time is worth .10 or .1
So the two equations are .05N+.1D=2 and N+D=25
I'm going to multiply 100 on both sides so I can clear the decimals from first equation giving me 5N+10D=200.
So I'm going to multiply the second by 5 giving my 5N+5D=125
Line up equations and you should see we can solve this system by elmination by subtracting the equations
5N+10D=200
5N+5D=125
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5D=75
D=75/5=15
So N+D=25 and D=15 so N=10.
