Answers

2016-08-02T22:20:35+08:00
Let x = the number of pcs for 20 cents;
      y= the number of pcs for 50 cents

x + y= 64 coins;

x=64-y..........................1.)

.2(x) + .5(y)= 18.50

.2 (64-y) + .5y =18.50;
12.8 -.2y + .5y=18.50

.3y= 5.7;
y=19 pcs of 5on cents.......ans..
x=64-19;
 =45 pcs. of 20 cents..

check;

.2(45) + .5 (19)=18.50
9 +9.5 =18.50
18.50=18.50
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