A refrigerator costs $580 a year to run. A family purchases a new one for $1200 that will save them 22% annually in energy costs. How many years does it take to pay for itself

It will take nine years and four months for the refrigerator to pay for itself.

Step-by-step explanation:

The new refrigerator which costs $1200, saves the family 22% annually in energy cost.

Since the old refrigerator costs $580 to run, we want to determine how many years it will take for 22% of $580 per year to make $1200.

22% of $580

= 580 × 0.22

= 127.6

That is, it saved then $127.6 per year.

Now,

$1200/127.6

≈ 9.4

Which means, it will take 9 years and 4 months for the refrigerator to pay for itself.

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m