How long has sonora held the account 4?

Question

Sonora currently has an account balance of $1,822.07. her initial deposit on the account was $781 and it earned 4.3% simple interest. How long has Sonora held the account?

Answer 1

Ok, so the formula for simple interest is A= P(1+rt)

 

A= Total Accrued Amount 

P= Principal Amount

R=Rate of interest per year

T= Time period 

 

So from the world problem we already have answers to three of these variables, the one thing we must solve for is Time. So First let's plug everything in, so it's easy to visualize:

 

A= 1822.07 (Sonora's account balance, or the the final amount that has accrued after the interest)

P= 781 (her initial, or principal, deposit)

R= .043(simple interest earned, always put it in decimal form)

T= How long has Sonora held the account? (This is what we are solving for)

 

So now we could switch around the entire equation to solve for T or just plug everything in first.

 

1822.07= 781(1+ .043t)   ----> multiply 781 by the numbers in the parentheses)

 

1822.07= 781 + 33.583t  -----> subtract 781 from both sides

  -781       -781

 

1041.07 = 33.583t     ---> divide each side by 33.583

 

t= 30.9999107  ------> round up

 

t= 31 years