420  Stamp
How many stamps? 1

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There are 180 stamps which are 4-cent stamps and 5-cent stamps. Altogether they cost 810 cents. How many 4-cent stamps are there?



There are 120 stamps which are 5-cent stamps and 9-cent stamps. Altogether they cost 800 cents. How many 5-cent stamps are there?



There are 200 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 680 cents. How many 3-cent stamps are there?



There are 150 stamps which are 6-cent stamps and 9-cent stamps. Altogether they cost 1140 cents. How many 6-cent stamps are there?



There are 140 stamps which are 5-cent stamps and 8-cent stamps. Altogether they cost 880 cents. How many 5-cent stamps are there?



There are 170 stamps which are 8-cent stamps and 9-cent stamps. Altogether they cost 1450 cents. How many 8-cent stamps are there?



There are 180 stamps which are 6-cent stamps and 8-cent stamps. Altogether they cost 1260 cents. How many 6-cent stamps are there?



There are 180 stamps which are 3-cent stamps and 6-cent stamps. Altogether they cost 840 cents. How many 3-cent stamps are there?



There are 250 stamps which are 3-cent stamps and 4-cent stamps. Altogether they cost 880 cents. How many 3-cent stamps are there?



There are 200 stamps which are 4-cent stamps and 7-cent stamps. Altogether they cost 1100 cents. How many 4-cent stamps are there?



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420    90 70 120 70 80 ( 430 )   80 90 80 120 100 ( 470 )   [[ 900 ]]