592  Stamp
How many stamps? 1

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There are 170 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 750 cents. How many 3-cent stamps are there?



There are 230 stamps which are 3-cent stamps and 9-cent stamps. Altogether they cost 1290 cents. How many 3-cent stamps are there?



There are 180 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1210 cents. How many 7-cent stamps are there?



There are 220 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 1020 cents. How many 7-cent stamps are there?



There are 210 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 930 cents. How many 6-cent stamps are there?



There are 140 stamps which are 4-cent stamps and 8-cent stamps. Altogether they cost 840 cents. How many 4-cent stamps are there?



There are 270 stamps which are 6-cent stamps and 9-cent stamps. Altogether they cost 1980 cents. How many 6-cent stamps are there?



There are 210 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 870 cents. How many 3-cent stamps are there?



There are 230 stamps which are 8-cent stamps and 3-cent stamps. Altogether they cost 1390 cents. How many 8-cent stamps are there?



There are 280 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 1360 cents. How many 3-cent stamps are there?



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592    110 130 130 90 100 ( 560 )   70 150 150 140 150 ( 660 )   [[ 1220 ]]