According to the rule of 72, which statement is true? an investment of $3,100 will double in 12 years at a compound interest rate of 5%. an investment of $9,000 will double in 10 years at a compound interest rate of 7%. an investment of $4,500 will double in 8 years at a compound interest rate of 9%. an investment of $3,000 will double in 4 years at a compound interest rate of 12%

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Question - According to the rule of 72, which statement is true? An investment of $3,100 will double in 12 years at a compound interest rate of 5%. An investment of $9,000 will double in 10 years at a compound interest rate of 7%. An investment of $4,500 will double in 8 years at a compound interest rate of 9%. An investment of $3,000 will double in 4 years at a compound interest rate of 12%

Answer - An investment of $3,000 will double in 4 years at a compound interest rate of 12%

0.012 / 3000 = 0.00004 = 4

the answer would be c:   ax + b = ax + c

step-by-step explanation:

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for