# Math Word Problems: Investment

• Aug 30th 2009, 07:46 PM
strigy
Math Word Problems: Investment
1.) An investor wishes to realize a return of 12% on a total of two investments. If he has $10,000 invested at 10%, how much additional money should be invested at 16%? 2.) A woman invested$25000 in two business ventures. Last year she made a profit of 15% from the first venture but lost 5% from the second venture. If last year's income from the two investments was equivalent to a return of 8% on the entire amount invested, how much had she invested in each venture?

Can you show me how it's done? I have the answers, I just don't know how to solve it. Thanks!
• Aug 30th 2009, 08:02 PM
pickslides
a 12% return on an amount x invested is $\displaystyle 1.12\times x$

10000 invested at 10% is 11000

I would try

$\displaystyle 11000+1.16\times (x-11000) = 1.12x$
• Aug 30th 2009, 08:03 PM
Wilmer
HINTS; 1st one:
Let x = amount @ 16%
.10(10000) + .16x = .12(10000 + x)

2nd one:
Let x = amount @ 15%
.15x - .05(25000 - x) = .08(25000)
• Aug 30th 2009, 08:20 PM
strigy
Ok, I see that my equations are the same. Thanks guys.

So, in summary:

.10(10000) + .16x = .12(10000 + x)
1000 + .16x = 1200 + .12x
.16x-.12x = 1200 - 1000
.04x = 200
x = 5000

.15x - .05(25000 - x) = .08(25000)
.15x - 1250 + .05x = 2000
.2x = 3250
x = 16250

Are those right?