831  Stamp
How many stamps? 1

Name : _________________

 

refresh

There are 250 stamps which are 8-cent stamps and 6-cent stamps. Altogether they cost 1740 cents. How many 8-cent stamps are there?



There are 170 stamps which are 8-cent stamps and 3-cent stamps. Altogether they cost 1010 cents. How many 8-cent stamps are there?



There are 260 stamps which are 7-cent stamps and 3-cent stamps. Altogether they cost 1340 cents. How many 7-cent stamps are there?



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



There are 220 stamps which are 7-cent stamps and 4-cent stamps. Altogether they cost 1180 cents. How many 7-cent stamps are there?



There are 220 stamps which are 3-cent stamps and 5-cent stamps. Altogether they cost 920 cents. How many 3-cent stamps are there?



There are 220 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 1720 cents. How many 7-cent stamps are there?



There are 200 stamps which are 8-cent stamps and 9-cent stamps. Altogether they cost 1710 cents. How many 8-cent stamps are there?



There are 170 stamps which are 3-cent stamps and 8-cent stamps. Altogether they cost 810 cents. How many 3-cent stamps are there?



There are 150 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 1100 cents. How many 7-cent stamps are there?



+(         )

 

(         )+

++[[          ]]++

831    120 100 140 70 100 ( 530 )   90 130 90 110 100 ( 520 )   [[ 1050 ]]