Volunteers at Sam's school use some of the student council's savings for a special project. They buy 3 backpacks for $9 each and fill each backpack with paper and pens that cost $4. By how much did the student council's savings change because of this project? The savings was changed by. dollars.

$39

Step-by-step explanation:

3 x 9 = 27

3 x 4 = 12

27 + 12 = 39

7 backpacks for $8 = $56

7 lots of paper and pens for $5 each = $35

56 + 35 = $91

The student Council savings decreased by $91.

Step-by-step explanation:

on monday rodney ate 1/4th of the sandwich = 3/12

on tuesday he ate 1/3rd of the sandwich = 4/12

therefore in total he has eaten = 3/12 + 4/12 = 7/12

thus we can say that he has eaten 7/12 of the sandwich on monday and tuesday alltogether.

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