Your friend is taking a class called Math for Everyday Living at another college. He (or she) is learning about compound interest, and his instructor simply gave the class the compound interest formula, A=P(1+r/n)nT without explaining how it is gotten. When your friend told you this in a letter, you were shocked! Write a letter to your friend (no longer than two pages) that explains step-by-step how the compound interest formula is gotten.

sine

step-by-step explanation:

college

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional