Emily had $56 in her account. she deposited a $265 check, and bought three equally priced backpacks for her children. the next day, when she checked her balance, it was $243. what was the price of each backpack?

$26

Step-by-step explanation:

Start with $56.

Add $265, obtaining a + balance of $321.

Let x represent the unit price of the backpacks.  Then:

$321 - 3x = $243.

Combining like terms:

3x = $78

Then x, the price of the individual backpack, was $78/3, or $26.

I'll do problem 12 to get you started

Part (a)

The ratio 3:6:7 means the three sides are 3x, 6x and 7x centimeters long. The x is some positive real number.

The longest side is 7x, which is also 16.1, so 7x = 16.1

Divide both sides by 7 to isolate x

7x = 16.1

7x/7 = 16.1/7

x = 2.3

Now we can calculate the other two sides

3x = 3*2.3 = 6.9

6x = 6*2.3 = 13.8

Part (b)

Add up the three sides to get

6.9 + 13.8 + 16.1 = 36.8