Simple interest doesn't compound, so we just find the interest she needs by dividing 4,000 by 8, and then divide that number by her principal to find the rate of interest.
4,000 ÷ 8 = 500
She needs 500 dollars per year in interest.
800 ÷ 14,100 = .0355 = 3.55%
Answer is B
To find an average you take the numbers to be averaged and add them together then You take the number and divide it by the number of numbers, in this case 4, and that gives you the average.
on this problem you want to do the opposite. you know the average she wants, an 87, so you multiply it by 4. 87*4=348. then you add the three numbers you have (88,81 and 87) and you get 256.
then you subtract 256 from 348 and you get 92. 92 is your answer to check just add 87+81+88+92=348
348/4=87
87 was the average she wanted.
Hope this helped! good luck :)
12. x= 4
13. x= 4
14. x= -1
Check the steps in the picture above
To solve for C, you have to get both of the numbers with a C on the same side. So, subtract the 5c from the right side onto the left side.

Then, divide by 3 on each side.

So, c = 7.