Answers

2016-03-06T22:27:04+08:00
(13) 1-peso coins and (17) 50-centavo coins

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  • Brainly User
2016-03-06T23:18:28+08:00
X + y = 30
      y = 30-x

Number of coins:
x = 1 peso 
30-x = 0.50 centavo coin

Equation:
1(x) + (30-x)(0.50)  = 21.50

x + 15 - 0.50x = 21.50

x - 0.50x = 21.50 - 15

0.50x = 6.50

0.50x/0.50 = 6.50/0.50

x = 13

Substitute 13 for x:
1 peso coin: x = 13 coins
50-centavo coin: 30-x = 30-13 = 17 coins

ANSWER:  13 pieces 1-peso coins and 17 pieces 50-centavo coins.

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