490  Stamp
How many stamps? 1

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There are 220 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 980 cents. How many 3-cent stamps are there?



There are 260 stamps which are 4-cent stamps and 6-cent stamps. Altogether they cost 1280 cents. How many 4-cent stamps are there?



There are 170 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1100 cents. How many 7-cent stamps are there?



There are 210 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 1230 cents. How many 7-cent stamps are there?



There are 200 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 810 cents. How many 6-cent stamps are there?



There are 230 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1640 cents. How many 6-cent stamps are there?



There are 130 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 440 cents. How many 3-cent stamps are there?



There are 150 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 910 cents. How many 7-cent stamps are there?



There are 210 stamps which are 8-cent stamps and 4-cent stamps. Altogether they cost 1240 cents. How many 8-cent stamps are there?



There are 130 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 900 cents. How many 6-cent stamps are there?



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490    140 140 80 150 70 ( 580 )   100 80 80 100 70 ( 430 )   [[ 1010 ]]