Question 381316
d=10 q=25 
d+q=24 .............................1
10d+25q=$3.75
3.75 = 375 cents
...
10d+25q=375.........................2
..
solve by addition
multiply (1) by -10
-10d-10q=-240
add it to (2)
25q-10q=375-240
15q=135
/15
q=135/15
q= 9 
...
plug value of q in 1
d+q=24
d+9=24
d=15
..
CHECK
10*15+9*25
=150+225
=375.

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