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365 Stamp |
Name : _________________ |
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There are 170 stamps which are 3-cent stamps and 9-cent stamps. Altogether they cost 810 cents. How many 3-cent stamps are there? |
There are 220 stamps which are 7-cent stamps and 9-cent stamps. Altogether they cost 1780 cents. How many 7-cent stamps are there? |
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| 365 120 140 120 110 150 ( 640 ) 100 90 100 140 120 ( 550 ) [[ 1190 ]] | ||
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