840  Stamp
How many stamps? 1

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There are 210 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 1020 cents. How many 6-cent stamps are there?



There are 240 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1550 cents. How many 7-cent stamps are there?



There are 210 stamps which are 8-cent stamps and 6-cent stamps. Altogether they cost 1500 cents. How many 8-cent stamps are there?



There are 180 stamps which are 4-cent stamps and 3-cent stamps. Altogether they cost 630 cents. How many 4-cent stamps are there?



There are 230 stamps which are 3-cent stamps and 9-cent stamps. Altogether they cost 1230 cents. How many 3-cent stamps are there?



There are 140 stamps which are 6-cent stamps and 5-cent stamps. Altogether they cost 780 cents. How many 6-cent stamps are there?



There are 200 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 670 cents. How many 3-cent stamps are there?



There are 230 stamps which are 5-cent stamps and 8-cent stamps. Altogether they cost 1510 cents. How many 5-cent stamps are there?



There are 190 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1280 cents. How many 6-cent stamps are there?



There are 190 stamps which are 5-cent stamps and 3-cent stamps. Altogether they cost 710 cents. How many 5-cent stamps are there?



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840    130 110 120 90 140 ( 590 )   80 130 110 120 70 ( 510 )   [[ 1100 ]]