412  Stamp
How many stamps? 1

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There are 140 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 690 cents. How many 6-cent stamps are there?



There are 280 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 1570 cents. How many 7-cent stamps are there?



There are 190 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 770 cents. How many 3-cent stamps are there?



There are 240 stamps which are 4-cent stamps and 9-cent stamps. Altogether they cost 1410 cents. How many 4-cent stamps are there?



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



There are 200 stamps which are 5-cent stamps and 6-cent stamps. Altogether they cost 1080 cents. How many 5-cent stamps are there?



There are 200 stamps which are 8-cent stamps and 7-cent stamps. Altogether they cost 1520 cents. How many 8-cent stamps are there?



There are 170 stamps which are 3-cent stamps and 7-cent stamps. Altogether they cost 910 cents. How many 3-cent stamps are there?



There are 280 stamps which are 3-cent stamps and 6-cent stamps. Altogether they cost 1230 cents. How many 3-cent stamps are there?



There are 170 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 810 cents. How many 6-cent stamps are there?



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412    90 150 140 150 100 ( 630 )   120 120 70 150 100 ( 560 )   [[ 1190 ]]