Answer:
what is it asking you? don't just show the problem tell us what needs to be done.
Answer:
w=7.8
Step-by-step explanation:
% change = (new value - old value)/(old value) * 100%
.. = (9.67 -9.74)/9.74 * 100%
.. = -0.07/9.74 * 100%
.. = -0.7%
The decrease is 0.7%.
Answer:
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.
