SOLUTION: Andrea saved Php370 from her allowance with denominations of 20-peso and 50-peso bills. She had 14 pieces of bills in all. How many did bills of each denomination she have?
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Question 1171048: Andrea saved Php370 from her allowance with denominations of 20-peso and 50-peso bills. She had 14 pieces of bills in all. How many did bills of each denomination she have? Answer by ikleyn(52781) (Show Source):
Let x be the number of the 50-peso bills;
then the number of the 20-peso bills is (14-x), OBVIOUSLY.
Then you write the total money equations
50x + 20*(14-x) = 370 peso.
Next, you simplify and solve this basic equation
50x + 280 - 20x = 370
50x - 20x = 370 - 280
30x = 90
x = 90/30 = 3.
ANSWER. 3 50-peso bills and the rest, 14-3 = 11 20-peso bills.
CHECK. 3*50 + 11*20 = 150 + 220 = 370 peso, total. ! Correct !
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