280  Stamp
How many stamps? 1

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There are 160 stamps which are 4-cent stamps and 5-cent stamps. Altogether they cost 720 cents. How many 4-cent stamps are there?



There are 270 stamps which are 6-cent stamps and 5-cent stamps. Altogether they cost 1490 cents. How many 6-cent stamps are there?



There are 230 stamps which are 4-cent stamps and 3-cent stamps. Altogether they cost 820 cents. How many 4-cent stamps are there?



There are 220 stamps which are 6-cent stamps and 7-cent stamps. Altogether they cost 1390 cents. How many 6-cent stamps are there?



There are 120 stamps which are 5-cent stamps and 8-cent stamps. Altogether they cost 750 cents. How many 5-cent stamps are there?



There are 170 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 830 cents. How many 7-cent stamps are there?



There are 170 stamps which are 5-cent stamps and 8-cent stamps. Altogether they cost 1000 cents. How many 5-cent stamps are there?



There are 150 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1060 cents. How many 6-cent stamps are there?



There are 260 stamps which are 5-cent stamps and 3-cent stamps. Altogether they cost 1080 cents. How many 5-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?



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280    80 140 130 150 70 ( 570 )   80 120 70 150 70 ( 490 )   [[ 1060 ]]