821  Stamp
How many stamps? 1

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There are 180 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 1110 cents. How many 7-cent stamps are there?



There are 210 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 730 cents. How many 3-cent stamps are there?



There are 180 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 1340 cents. How many 7-cent stamps are there?



There are 240 stamps which are 3-cent stamps and 5-cent stamps. Altogether they cost 980 cents. How many 3-cent stamps are there?



There are 230 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 800 cents. How many 3-cent stamps are there?



There are 150 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 1170 cents. How many 7-cent stamps are there?



There are 240 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 1110 cents. How many 6-cent stamps are there?



There are 180 stamps which are 3-cent stamps and 5-cent stamps. Altogether they cost 640 cents. How many 3-cent stamps are there?



There are 190 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 1170 cents. How many 7-cent stamps are there?



There are 210 stamps which are 5-cent stamps and 3-cent stamps. Altogether they cost 790 cents. How many 5-cent stamps are there?



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821    130 110 100 110 120 ( 570 )   90 130 130 110 80 ( 540 )   [[ 1110 ]]