Carolyn received a check last week . She invested part at 15% and 1000 more than this amount at 16%. If she will earn $780 in interest in a year, how much was invested at each rate?

$2,000 was invested at 15% rate.

$3,000 was invested at 16% rate.

Step-by-step explanation:

Carolyn received a check last week.

She invested part at 15%  and;

$1000 more than this amount at 16%

She will earn simple interest of $780 in one year.

Simple interest formula is;

I = PRT

Where I is the interest, P is the amount invested, R is the rate and T is the time.

Interest earned here = $x × × 1 = $0.15x

Interest earned here = ($x + $1000) × × 1 = $0.16x + $160

$0.15x + $0.16x + $160 = $780

$0.31x = $780 - $160 = $620

$x = $620 ÷ 0.31 = $2000

So the amount invested at 15% rate was $2000 and;

The amount invested at 16% rate was $2000 + $1000 = $3000

add all the numbers and check the ones place.

the answer is 486. as the ones place is more than 4, the estimation will be the next 10 ie, 490

step-by-step explanation:

3024 rhe base is what up in worry about