445  Stamp
How many stamps? 1

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There are 150 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 810 cents. How many 7-cent stamps are there?



There are 220 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1440 cents. How many 7-cent stamps are there?



There are 140 stamps which are 4-cent stamps and 7-cent stamps. Altogether they cost 740 cents. How many 4-cent stamps are there?



There are 230 stamps which are 3-cent stamps and 8-cent stamps. Altogether they cost 1240 cents. How many 3-cent stamps are there?



There are 170 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 990 cents. How many 7-cent stamps are there?



There are 240 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1660 cents. How many 6-cent stamps are there?



There are 170 stamps which are 4-cent stamps and 8-cent stamps. Altogether they cost 960 cents. How many 4-cent stamps are there?



There are 210 stamps which are 6-cent stamps and 9-cent stamps. Altogether they cost 1620 cents. How many 6-cent stamps are there?



There are 200 stamps which are 6-cent stamps and 5-cent stamps. Altogether they cost 1140 cents. How many 6-cent stamps are there?



There are 170 stamps which are 8-cent stamps and 7-cent stamps. Altogether they cost 1270 cents. How many 8-cent stamps are there?



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445    90 120 80 120 120 ( 530 )   130 100 90 140 80 ( 540 )   [[ 1070 ]]