678  Stamp
How many stamps? 1

Name : _________________

 

refresh

There are 170 stamps which are 5-cent stamps and 6-cent stamps. Altogether they cost 900 cents. How many 5-cent stamps are there?



There are 220 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 1320 cents. How many 7-cent stamps are there?



There are 180 stamps which are 6-cent stamps and 3-cent stamps. Altogether they cost 900 cents. How many 6-cent stamps are there?



There are 210 stamps which are 5-cent stamps and 9-cent stamps. Altogether they cost 1530 cents. How many 5-cent stamps are there?



There are 140 stamps which are 3-cent stamps and 9-cent stamps. Altogether they cost 720 cents. How many 3-cent stamps are there?



There are 200 stamps which are 8-cent stamps and 6-cent stamps. Altogether they cost 1420 cents. How many 8-cent stamps are there?



There are 270 stamps which are 5-cent stamps and 8-cent stamps. Altogether they cost 1740 cents. How many 5-cent stamps are there?



There are 140 stamps which are 6-cent stamps and 7-cent stamps. Altogether they cost 910 cents. How many 6-cent stamps are there?



There are 200 stamps which are 5-cent stamps and 8-cent stamps. Altogether they cost 1330 cents. How many 5-cent stamps are there?



There are 150 stamps which are 5-cent stamps and 4-cent stamps. Altogether they cost 690 cents. How many 5-cent stamps are there?



+(         )

 

(         )+

++[[          ]]++

678    120 110 120 90 90 ( 530 )   110 140 70 90 90 ( 500 )   [[ 1030 ]]