Answer:
100.7%
Step-by-step explanation:
Since the interest is compounded quarterly, and there are 4 quarters per year, that would leave us with 32 quarters total where interest is acquired. Now, we need to find the interest rate, that would be required in order to end up with 420 dollars after 32 quarters.
We can setup a formula using our period of time and the money he invested into the bank:

We can divide 340 from both sides, and simplify the right side to 21 divided by 17:

Taking the 32th root of 21/17 is equal to 1.00662, which is equal to 100.0662%. To the nearest tenth of a percent, this is equal to 100.7%.
The next number is 38. The pattern is 7, 16, 8, 27, 9; if you look at the first 4 numbers, you notice that it counts to 7, 8, 9. Then you have 16 and 27, if the pattern continues; the next number is 38.
When you see the equals sign with a squiggly line on top, you know that the items on each side of the equation are congruent. Next, name the corresponding sides. Corresponding sides are matching sides between two triangles. They will have the same length in congruent triangles