909  Stamp
How many stamps? 1

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There are 220 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 1620 cents. How many 7-cent stamps are there?



There are 250 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 1270 cents. How many 3-cent stamps are there?



There are 170 stamps which are 8-cent stamps and 4-cent stamps. Altogether they cost 1040 cents. How many 8-cent stamps are there?



There are 260 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 1560 cents. How many 7-cent stamps are there?



There are 180 stamps which are 4-cent stamps and 7-cent stamps. Altogether they cost 900 cents. How many 4-cent stamps are there?



There are 260 stamps which are 4-cent stamps and 6-cent stamps. Altogether they cost 1300 cents. How many 4-cent stamps are there?



There are 230 stamps which are 4-cent stamps and 6-cent stamps. Altogether they cost 1100 cents. How many 4-cent stamps are there?



There are 190 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 990 cents. How many 6-cent stamps are there?



There are 160 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1050 cents. How many 7-cent stamps are there?



There are 230 stamps which are 8-cent stamps and 6-cent stamps. Altogether they cost 1620 cents. How many 8-cent stamps are there?



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909    140 120 90 130 120 ( 600 )   130 140 140 90 120 ( 620 )   [[ 1220 ]]