An investor receives a total combined return of 7% on his two differen

Question

An investor receives a total combined return of 7% on his two different investments. On his $10,000 investment he receives a return of 6%. What is the return on his $20,000 investment?

A. 7.25%
B. 7.5%
C. 8%
D. 8.5%
E. 9%

Mbawarrior01 · Answer

Ans : B => 7.5%

7 % of 30000 = 6 % of 10000 + x % of 20000

CounterSniper · Answer

total investment = $30000
on which he receives 7% = 2100
now,
on his $10000 he receives 6% = $600
remaining $1500
which is (1500/20000)*100 = 7.5

mohshu · Answer

0.06 * 10000 + 20000x = 0.07(30000)
solving for x give x = 7.5%
option B

abrahamic · Answer

Another quick short at this question will be:
What number can we multiply by 2 that when added to 6% and averaged we will get 7%? (Given that $20,000 is twice $10,000)
i.e. let x be that number, 
So, (6% + (2x)%)/3 = 7
Hence, 6% + (2x)% = 21
Then (2x)% = 21-6 = 15
 x = (15/2)% = 7.5%

generis · Answer

Take two zeros off the amounts for easier arithmetic. The weighted terms remain the same, proportionally.

Sometimes split interest problems can be treated as mixture problems. Two quantities at two different interest rates equal an overall or "average" interest rate of 7% on the two investments, summed.

6 percent return on 100
x percent return on 200
7 percent return on total, which is 100 + 200 = 300

.06(100) +  \frac{x}{100} (200) = .07(300)

6 +  \frac{200x}{100}  = 21

6 + 2x = 21
2x = 15
x = 7.5 (percent, accounted for in  \frac{x}{100} )

Answer B

pushpitkc · Answer

Total return on investment is 7%, for investment - 30000$, which is 2100$.

Since he makes 6%(600$) from the initial investment of 10000$,
he would have to make 1500$ from the other 20000$ invested.

\frac{1500}{20000}*100  = 7.5%
Since we have been asked to find the return on his investment, the percentage would be  7.5%(Option B)

shashankism · Answer

Let the amount 20000 be invested at x% return.

So, Total interest received = 6/100* 10000 x/100 * 20000 = 200x + 600

Total investment = 30000

Total interest received = 7/100 * 30000 = 2100

-> 2100 = 200x +600 
-> x = 7.5% 
 
Answer B

ScottTargetTestPrep · Answer

We let the return of his $20,000 investment be p percent and create the following equation:

(6/100)(10,000) + (p/100)(20,000) = (7/100)(10,000 + 20,000)

600 + 200p = 2,100

200p = 1,500

p = 7.5

Answer: B

BrentGMATPrepNow · Answer

The investor invested a total of $30,000, and his combined return is 7%. 
7% of $30,000 = $2100
So, the investor made a total profit of   $2100

The $10,000 investment received a return of 6%
6% of $10,000 =  $600

$2100   -  $600  =   $1500  
This means the $20,000 investment must have made a profit of   $1500  
  $1500  /$20,000 = 15/200 = 7.5/100 = 7.5%
So the investor received a 7.5% return on his $20,000 investment

Answer: B

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An investor receives a total combined return of 7% on his two differen

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