717  Stamp
How many stamps? 1

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There are 230 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 1280 cents. How many 7-cent stamps are there?



There are 240 stamps which are 6-cent stamps and 9-cent stamps. Altogether they cost 1800 cents. How many 6-cent stamps are there?



There are 220 stamps which are 3-cent stamps and 9-cent stamps. Altogether they cost 1080 cents. How many 3-cent stamps are there?



There are 240 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 1860 cents. How many 7-cent stamps are there?



There are 230 stamps which are 8-cent stamps and 6-cent stamps. Altogether they cost 1580 cents. How many 8-cent stamps are there?



There are 230 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 1220 cents. How many 7-cent stamps are there?



There are 200 stamps which are 8-cent stamps and 4-cent stamps. Altogether they cost 1360 cents. How many 8-cent stamps are there?



There are 150 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 850 cents. How many 7-cent stamps are there?



There are 270 stamps which are 8-cent stamps and 4-cent stamps. Altogether they cost 1640 cents. How many 8-cent stamps are there?



There are 190 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 840 cents. How many 6-cent stamps are there?



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717    120 120 150 150 100 ( 640 )   100 140 100 140 90 ( 570 )   [[ 1210 ]]