SOLUTION: John Craig invested a portion of $15,000 at 10% annual interest and the balance at 6% annual interest. If he earned $1260 for the year from the two accounts, how much did he inves

Question 61422: John Craig invested a portion of $15,000 at 10% annual interest and the balance at 6% annual interest. If he earned $1260 for the year from the two accounts, how much did he invest at 10%?
Answer by tutorcecilia(2152) (Show Source): You can put this solution on YOUR website!
Ax+By=C [use the standard form of a line]
10%x+6%y=$1260
.10x+.06y=1260 [convert the percents to decimals]
and
x+y=$15,000
x+($15,000-x)=$15,000
putting it all together gives:
.10x+.06(15,000-x)=1260 [substitute (15,000-x) for y]
.10x+900-.06=1260
.04x=360
x=$9000 invested at 10%
y=(15,000-x)=15,000-9000=$6,000 invested at 6%
because $6,000+$9,000=$15,000
and
.10(9000)=$900
.06(6,000)=$360
900+360=$1260

RELATED QUESTIONS
John invested a portion of 15,000 at 10 percent annual interest rate and the balance at 6 (answered by richwmiller)

John invested a portion of $15,000 at 10% annual interest and the rest at 6% annual... (answered by mananth,lmeeks54)

Helllo, I need help with this word problem: Mrs. Lambert invested a portion of... (answered by checkley75)

Hello, I'm having trouble with this word problem: Wendell invested a portion of (answered by ptaylor)

the total interest earned after one year Php 100 000 is invested, part of 6% annual... (answered by ikleyn)

the total interest earned after one year Php 100 000 is invested, part of 6% annual... (answered by greenestamps)

Brandon invested $20 000. He invested part of the money in a term deposit paying 4%... (answered by ikleyn,greenestamps)

John invested $10,000, part at 5% and the rest at 6.5% interest. How much did he invest... (answered by richwmiller)

An executive invests $28,000, some at 6% and the rest at 4% annual interest. If he... (answered by ikleyn,greenestamps)