Kayla bought seven boxes. A week later, half of all her boxes were destroyed in a fire. There are now only 22 boxes left. With how many did she start? Show your work.

Let's call the number of boxes Maria started with:

There are 37 boxes

Step-by-step explanation:

Let's call the number of boxes Kayla started with:

Then we can write:

22

=

b

+

7

2

Where:

22

is the number of boxes Kayla has left.

(

b

+

7

)

is the number of boxes Kayla started with plus the

7

she bought

The division by

2

represents

1

2

of the total boxes Kayla had being destroyed by fire.

We can solve this by first multiplying each side of the equation by

2

to eliminate the fraction while keeping the equation balanced:

2

×

22

=

2

×

b

+

7

2

44

=

2

×

b

+

7

2

44

=

b

+

7

Now, subtract

7

from each side of the equation to solve for

b

while keeping the equation balanced:

44

−

7

=

b

+

7

−

7

37

=

b

+

0

37

=

b

b

=

37

Kayla started out with 37 boxes.

one that is bigger than 3 1/2