I believe this is the right way to write the function
N = [log A − log P] / log(1.0175)
N =[ log (1210.26) - log (1000)]/log (1.0175)
N =log [1210.26/1000] / log (1.0175) = log (1.21026)/log(1.0175) = 0.08288/0.00753 = 11
N = 11 months
-18 because a negative number times positive is negative.
~JZ
Answer : 96
x – y = 16
--------> equation 1

x is the higher grade and y is the lower grade
We solve the first equation for y
x - y = 16
-y = 16 -x ( divide each term by -1)
y = -16 + x
Now substitute y in second equation



Take common denominator to combine fractions


Add 8 on both sides

Multiply both sides by 
x = 96
We know x is the higher grade
96 is the higher grade of Jose’s two tests.