There are 140 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 880 cents. How many 7-cent stamps are there?
There are 200 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1310 cents. How many 7-cent stamps are there?
There are 130 stamps which are 4-cent stamps and 7-cent stamps. Altogether they cost 670 cents. How many 4-cent stamps are there?
There are 150 stamps which are 5-cent stamps and 7-cent stamps. Altogether they cost 850 cents. How many 5-cent stamps are there?
There are 180 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 860 cents. How many 3-cent stamps are there?
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There are 230 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 1710 cents. How many 7-cent stamps are there?
There are 230 stamps which are 8-cent stamps and 9-cent stamps. Altogether they cost 1950 cents. How many 8-cent stamps are there?
There are 140 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 840 cents. How many 7-cent stamps are there?
There are 260 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 2080 cents. How many 7-cent stamps are there?
There are 250 stamps which are 4-cent stamps and 3-cent stamps. Altogether they cost 900 cents. How many 4-cent stamps are there?
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