690  Stamp
How many stamps? 1

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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 150 stamps which are 3-cent stamps and 5-cent stamps. Altogether they cost 550 cents. How many 3-cent stamps are there?



There are 240 stamps which are 8-cent stamps and 7-cent stamps. Altogether they cost 1830 cents. How many 8-cent stamps are there?



There are 210 stamps which are 3-cent stamps and 5-cent stamps. Altogether they cost 750 cents. How many 3-cent stamps are there?



There are 210 stamps which are 6-cent stamps and 5-cent stamps. Altogether they cost 1180 cents. How many 6-cent stamps are there?



There are 190 stamps which are 6-cent stamps and 5-cent stamps. Altogether they cost 1030 cents. How many 6-cent stamps are there?



There are 190 stamps which are 6-cent stamps and 4-cent stamps. Altogether they cost 1000 cents. How many 6-cent stamps are there?



There are 160 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 850 cents. How many 7-cent stamps are there?



There are 230 stamps which are 8-cent stamps and 4-cent stamps. Altogether they cost 1320 cents. How many 8-cent stamps are there?



There are 150 stamps which are 5-cent stamps and 4-cent stamps. Altogether they cost 670 cents. How many 5-cent stamps are there?



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690    120 100 150 150 130 ( 650 )   80 120 70 100 70 ( 440 )   [[ 1090 ]]