Question

Larry Mitchell invested part of his $ 35 comma 000$35,000 advance at 4 %4% annual simple interest and the rest at 9 %9% annual simple interest. If his total yearly interest from both accounts was $ 3 comma 100$3,100​, find the amount invested at each rate.

Answer 1

$1,000; $34,000

Step-by-step explanation:

Total investment = $35,000

Total yearly interest from both accounts = $3,100

Let the amount invested at 4% be x,

Amount invested at 9% = $35,000 - x

Simple interest = Principle × Rate of interest × Time period

$3,100 = (x × 0.04 × 1) + [($35,000 - x) × 0.09 × 1]

$3,100 = 0.04x + ($35,000 × 0.09) - 0.09x

$3,100 = 0.04x + $3,150 - 0.09x

0.05x = $50

x = $1,000

Therefore,

Amount invested at 4% = x = $1,000

Amount invested at 9% = $35,000 - x

= $35,000 - $1,000

= $34,000