interest problem

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interest problem

by galit_d2d » Sun Apr 20, 2008 2:57 pm
another problem brought from the math review

a total of 1200$ is deposited in 2 semi annual accounts for one year. part at 5% and remainder at 10% . If 72$ was earned as interest How much was deposited at 5%?

the equation is :
72=x*5*0.5/100 + (1200-x)*10*0.5/100

well, I understood this...but...after solving this I got an answer with (-):
-480?
can this be correct?...
help...please...
Source: — Problem Solving |

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by kandyhot27 » Sun Apr 20, 2008 5:40 pm
your equation is wrong

(P*0.05*1) + [(1200-P)*0.1*1] = 72

Solve
P = 960 in 5% account

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by galit_d2d » Mon Apr 21, 2008 12:42 am
th can you explain me your way of creating this equation?because I don't understand this...

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by gmatguy16 » Mon Apr 21, 2008 2:26 pm
semi annual ,does that not mean its a compound interest scenario and not simple interest ,what are the answer choices please

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by galit_d2d » Mon Apr 21, 2008 3:42 pm
there were no choices, just the equation I wrote above,

also...
the time period does it give preposition like:
1:1?
or should I put 1/2 of a year like in the first equation?

and well, it worked with the new equation, thanx:)

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by luvaduva » Tue Apr 22, 2008 4:54 pm
It does mean compound interest, but the problem becomes MUCH more time consuming if you try to solve it using compound.

From what I have seen, even if a problem asks for compound you can use the simple and pick the answer that is very close to it.

Kandyhot27's answer is correct *enough*