724  Stamp
How many stamps? 1

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There are 200 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1320 cents. How many 7-cent stamps are there?



There are 220 stamps which are 4-cent stamps and 6-cent stamps. Altogether they cost 1120 cents. How many 4-cent stamps are there?



There are 140 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 490 cents. How many 3-cent stamps are there?



There are 230 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 1730 cents. How many 7-cent stamps are there?



There are 230 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 1090 cents. How many 3-cent stamps are there?



There are 220 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 940 cents. How many 3-cent stamps are there?



There are 250 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 2010 cents. How many 7-cent stamps are there?



There are 210 stamps which are 6-cent stamps and 9-cent stamps. Altogether they cost 1590 cents. How many 6-cent stamps are there?



There are 140 stamps which are 4-cent stamps and 8-cent stamps. Altogether they cost 800 cents. How many 4-cent stamps are there?



There are 130 stamps which are 6-cent stamps and 7-cent stamps. Altogether they cost 840 cents. How many 6-cent stamps are there?



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724    120 100 70 110 130 ( 530 )   150 120 100 80 70 ( 520 )   [[ 1050 ]]