Hiro bought a five-pack of rechargeable batteries last week and an eight-pack

of the same type of batteries this week. He knows the cost of each battery is

the same no matter how many are in a pack. If Hiro spent $5.55 more on the

eight-pack than on the five-pack, how much would a ten-pack cost?

Step-by-step explanation:

Let x represent the cost of each battery since the cost of each battery is the same no matter how many are in a pack.

Hiro bought a five-pack of rechargeable batteries last week and an eight-pack of the same type of batteries this week. It means that the cost of the 5 pack battery is $5x and the cost of the 8 pack battery is $8x.

If Hiro spent $5.55 more on the

eight-pack than on the five-pack, it means that

8x = 5x + 5.5

8x - 5x = 5.5

3x = 5.5

x = 5.5/3 = 1.83

The cost of a 10 pack battery would be

1.83 * 10 = $18.3

All the batteries cost the same, and he spent 5.55 more on an 8 pack than a 5 pack.

That's a 3 battery difference and 5.55 difference, so let's divide and get the unit rate for the batteries

5.55/3=1.85

Then, find the cost of a 10 pack by multiply 1.85 by 10

1.85*10=18.5

So a 10 pack costs $18.50