Question

Phil has $20,000, part of which he invests at 8% interest and the rest at 6%. If the total income from the two investments was $1460, how much did he invest at 6%?

Answer 1

Answer: 7000

Explanation:

Let the amount invested in 8% account be P1 and the amount invested in 6% account be P2

. If the total amount invested is $20,000 then:

P1+P2=20,000. (Eq. 1)

The interest earned in one year from the 8% account is:

I1=0.08P1

and the interest earned in one year from the 6% account is:

I2=0.06P2

If the total interest earned is $1460, then:

I1+I2=1460

0.08P1+0.06P2=1460

(Eq. 2) From Eq. 1 :

P1=20000−P2

Substituting this into Eq. 2:

0.08 (20000−P2) + 0.06P2 = 1460

1600 − 0.08P2 + 0.06P2 = 1460

0.02P2 = 140

P2 = 140 / 0.02

P2 = 7000

Hence, he invested $7000 at the rate of 6%.