Help please will fan and medal!!

Kenneth started saving for retirement at age 40 with plans to retire at 70. He invested an average of $400 per month in various securities, with an average annual return of 7% adjusted for inflation. Assuming monthly compounding, how much has Kenneth saved at the started of retirement?
.
A. $487,988.40
B. $720,421.84
C. $37,784.31
D. $556,559.83

Question

Help please will fan and medal!!

Kenneth started saving for retirement at age 40 with plans to retire at 70. He invested an average of $400 per month in various securities, with an average annual return of 7% adjusted for inflation. Assuming monthly compounding, how much has Kenneth saved at the started of retirement?
.
A. $487,988.40
B. $720,421.84
C. $37,784.31
D. $556,559.83

flashp · Answer

What do you think it is @killer_sweetness97

anonymous · Answer

p*((1+r/n)^nt-1)/(r/n) but  first check with 1 year and verify the formula or variables

anonymous · Answer

or here ....  t=30 and n=12 as it is monthly compounding

anonymous · Answer

it may be p=400 r=0.07 n=12 t=30 im not sure anymore

anonymous · Answer

I figured it out but thank you both it was A