678  Stamp
How many stamps? 1

Name : _________________

 

refresh

There are 180 stamps which are 7-cent stamps and 6-cent stamps. Altogether they cost 1200 cents. How many 7-cent stamps are there?



There are 200 stamps which are 8-cent stamps and 3-cent stamps. Altogether they cost 1050 cents. How many 8-cent stamps are there?



There are 160 stamps which are 3-cent stamps and 6-cent stamps. Altogether they cost 660 cents. How many 3-cent stamps are there?



There are 260 stamps which are 8-cent stamps and 7-cent stamps. Altogether they cost 1970 cents. How many 8-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?



There are 230 stamps which are 8-cent stamps and 9-cent stamps. Altogether they cost 1960 cents. How many 8-cent stamps are there?



There are 200 stamps which are 8-cent stamps and 4-cent stamps. Altogether they cost 1280 cents. How many 8-cent stamps are there?



There are 190 stamps which are 7-cent stamps and 5-cent stamps. Altogether they cost 1090 cents. How many 7-cent stamps are there?



There are 170 stamps which are 8-cent stamps and 5-cent stamps. Altogether they cost 1180 cents. How many 8-cent stamps are there?



There are 190 stamps which are 7-cent stamps and 8-cent stamps. Altogether they cost 1420 cents. How many 7-cent stamps are there?



+(         )

 

(         )+

++[[          ]]++

678    120 90 100 150 100 ( 560 )   110 120 70 110 100 ( 510 )   [[ 1070 ]]