Ok here is the problem



brent lent his bro bob some money at 8% simple interest and he lent his sis betty half as much money at twice the intrest rate.

Both loans are for 1 year. If brent made a total of .24 cents in interest, then how much did he lend to each one.




you don't have to tell me the answer just how to figure out the problem.

thanks!

 

http://math.about.com/od/businessmath/ss/Interest.htm

 

MMM's link should help you.

Hints: It's a single variable equation. The interest Brent made is the sum of 2 products.

 

Interest = Principle x Rate x Time

In this case, it's:

Brents Interest = (Bob Principle x .08 x 1) + (Betty Principle x .16 x 1)

So let's put this into an actual formula now:

.24 = (A x .08 x 1) + [(1/2 x A) x .16 x 1)]

Now distribute the variable:

.24 = .08A + .08A

Now combine:

.24 = .16A

Divide:

.24 / .16 = A

Answer for A is $1.50

Now let's check the work by putting 1.5 in for A:

.24 = (1.5 x .08 x 1) + [(1/2 x 1.5) x .16 x 1)]

Simplify:

.24 = .12 + .12

.24 = .24

Success! So the final answer is that Brent lent Bob $1.50 and Betty $0.75

If you have any more Algebra questions, feel free to ask.

 

As Barbie said, "Math is hard."  

 

And so is Ken's ugh... yeah.

 

I wish I had the internet when I was in highschool.

 

Me grimlock no bozo it just head hurts when me think!

 

Aw, come on! This was an easy one!  

 

Ken doesn't even HAVE one!

 

Try this one:

A building has a heat loss coefficient of 17 kW/K and an effective thermal capacity of 1.8 GJ/K. The internal set point temperature is 20oC and the building is occupied for 12 hours per day (7 days per week) and has an installed plant capacity of 500 kW. For a mean monthly outdoor temperature of 7oC (when the preheat time, t3-t2 = 4.71 hours) determine the following:

(i) The summation of all hourly indoor temperatures overnight
(ii) the mean 24 hour indoor temperature
(iii) the base temperature if mean gains are 90 kW
(iv) monthly degree-days using Hitchin’s formula, assuming k = 0.71 and 31 days in the month
(v) the fuel consumption for that month (assuming an overall plant efficiency of 0.75)
(vi) The CO2 emissions for that month (take the CO2 factor as 0.19 kg/kWh)

 

I could give you the answer, but you'd only be hurting yourself when you took it.

 

I don't do energy.  

 

Actually, I know the answers.

Chicken.

 

Just messing with you, guy  

 

Insufficient information. How many people are coming in and out through the day? What's the average occupancy rate? How much heat is lost through doors opening and closing by the occupants?

Besides, this is more a physics problem than a math problem, as many physics formulae are involved.

 

None of that information is needed actually.

 

When you're done with Boardwise's problem, try this one:

Two random variables X and Y have the joint PDF

fxy(x,y) = 6x if x>0, 0<x+y <1 ...and 0 otherwise

1. Find the marginal PDFs of X and Y
2. Find the expected value E{XY}
3. Find the probability of the event {X < 1/2, Y< 3/4}

 

Once upon a time I went to an engineering school...

...but I couldn't do that stuff then either.