370  Stamp
How many stamps? 1

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There are 190 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 680 cents. How many 3-cent stamps are there?



There are 170 stamps which are 3-cent stamps and 6-cent stamps. Altogether they cost 690 cents. How many 3-cent stamps are there?



There are 160 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1120 cents. How many 6-cent stamps are there?



There are 160 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1140 cents. How many 6-cent stamps are there?



There are 160 stamps which are 5-cent stamps and 9-cent stamps. Altogether they cost 1120 cents. How many 5-cent stamps are there?



There are 210 stamps which are 6-cent stamps and 7-cent stamps. Altogether they cost 1380 cents. How many 6-cent stamps are there?



There are 170 stamps which are 8-cent stamps and 9-cent stamps. Altogether they cost 1440 cents. How many 8-cent stamps are there?



There are 210 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 910 cents. How many 3-cent stamps are there?



There are 210 stamps which are 8-cent stamps and 5-cent stamps. Altogether they cost 1410 cents. How many 8-cent stamps are there?



There are 120 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 890 cents. How many 7-cent stamps are there?



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370    80 110 80 70 80 ( 420 )   90 90 140 120 70 ( 510 )   [[ 930 ]]