an apple cost 20 cent and a orange cost 25cent. if the total number of apples and oranges is 20 and the total cost is 4.55, how many oranges are there?
A = # apples @ $0.20 each.
O = # organbes @ $0.25 each.
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equation 1 is A + O = 20
equation 2 is 0.20 + 0.25 O = 4.55
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Solve the two equations simultaneously.
Post your work if you get stuck.