x ten cent pieces
(28-x) twenty cent pieces
10 x + 20(28-x) = 430
10 x + 560 - 20 x = 430
10 x = 130
x = 13
28-x = 15
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x= boys
x-4 = girls
2x-4 = 26
x = 15
x-4 = 11
Mark has 28 10-cent and 20-cent pieces. How many of each coin does he have if their total value is $4.30?
In a class of 26 students, there are four more than girls. How many boys are there?
1 answer
1 answer