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Dennis mowed his next door neighbors lawn for a handful of dimes and nickels 80 coins in all. Upon completing the job he counted out the coins and it came to $6.60. How many of each coins did he earn

Respuesta :

D- dimes
N-nickels
D+N=80
10d+5n=660
N=80-d
10d+5(80-d)=660
10d+400-5d=660
5d=660-400
5d=260
260 divided by 5 is 52

52 dimes and 28 nickels

Following are the calculation of the coins:

Given:

dimes and nickels  coins= 80

counted coins= 6.60

To find:

calculated coins=?

Solution:

Let  

N= number of Nickeles  

D= number of Dimes

[tex]\bold{N+D=80}\\\\\bold{N=(80-D)}[/tex]

calculate the dimes:

[tex]\bold{0.05N+0.10D= 6.60}\\\\\bold{0.05(80-D)+0.10D= 6.60}\\\\\bold{4 -0.05 D+0.10D= 6.60}\\\\\bold{4 +0.05D= 6.60}\\\\\bold{0.05D= 6.60-4}\\\\\bold{0.05D= 2.60}\\\\\bold{D= \frac{2.60}{0.05}\ = 52 \ dimes}[/tex]

Calculating the nickels:  

[tex]\bold{n=80-d}\\\\\bold{n=80-52}\\\\\bold{n=28 \ nickels }[/tex]

Therefore, the answer is "52 dimes and 28 nickels"

Learn more:

brainly.com/question/11891960

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