The rate a computer works is 1/time. Working together, you add the rates.
Let new computer be x, old computer be y.
x = y - 7

Rounded to nearest tenth gives:
x = 23 hours
Answer:
the answer is 7.33
Step-by-step explanation:
I used a calculator
Answer:
h=A/b
Step-by-step explanation:
Think of putting number in the place of the letter, for example
A is 4
b is 2
h is 2
4=2 x 2 then plug the numbers in the right spot
2=4/2 then see what can be rearranged or what is left to make the
equation true
The two #'s are 156 and 4.
When you multiply 156*4=624.
When you add them together 156+4=160
You can also check you're work using a calculator.