Question 979652


The system of equation is 


{{{system(n + d = 22,
0.05*n + 0.10*d = 1.45)}}}.


To solve it, &nbsp;express &nbsp;<B>n</B>&nbsp; from the first equation and substitute into the second one. &nbsp;You will get


n = 22 - d, &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;--->


0.05*(22-d) + 0.1*d = 1.45,


Solve the last equation by simplifying it step by step:


1.10 - 0.05*d + 0.1*d = 1.45,


(0.1 - 0.05)*d = 1.45 - 1.10,


0.05*d = 0.35,


d = {{{0.35/0.05}}} = 7.


Thus we find the number of dimes: &nbsp;d = 7.

Now, &nbsp;the number of nickels is &nbsp;d = 22 - 7 = 15.


<U>Check</U>: &nbsp;5*15 + 7*10 = 75 + 70 = 145 = $1.45. 


<B>Answer</B>. &nbsp;15 nickels &nbsp;and &nbsp;7 dimes.