To solve the first question, which is asking for the total amount of money, we have to add what Yvonne started with, with how much she earned.
4,000+960=4,960.
Now for the second question. It is asking for the unit rate of interest earned per year. So we have to divide 960 with the amount of years, which is 3.
960/3=320.
For the last question. 1 percent of 320 is 3.2, so we add 320 with 3.2 to increase the rate. Then we'll multiply the sum with 3 to find how much she would've earned. Finally, we'll add the amount with the 4,000 she started with.
320+3.2=323.2
323.2x3=969.6
4,000+969.6=4,969.6
So the answers are:
How much does she have in her account at the end of 3 years? $4,960
At what annual simple interest rate did the account grow? $320 per year
How many more dollars would she have in her account if the interest rate were 1% greater? 4,969.6
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sorry if this doesn't help