411  Stamp
How many stamps? 1

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There are 210 stamps which are 3-cent stamps and 9-cent stamps. Altogether they cost 1350 cents. How many 3-cent stamps are there?



There are 170 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 980 cents. How many 7-cent stamps are there?



There are 160 stamps which are 3-cent stamps and 5-cent stamps. Altogether they cost 640 cents. How many 3-cent stamps are there?



There are 180 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1160 cents. How many 7-cent stamps are there?



There are 190 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1320 cents. How many 6-cent stamps are there?



There are 180 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 900 cents. How many 3-cent stamps are there?



There are 200 stamps which are 6-cent stamps and 7-cent stamps. Altogether they cost 1310 cents. How many 6-cent stamps are there?



There are 170 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 790 cents. How many 7-cent stamps are there?



There are 150 stamps which are 5-cent stamps and 7-cent stamps. Altogether they cost 910 cents. How many 5-cent stamps are there?



There are 200 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 1540 cents. How many 7-cent stamps are there?



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