Answer:
Step-by-step explanation:
Use the basic simple interest formula:
P * r * t = I and put the info into a table with those variables along the top, formig the columns we need:
P * r * t = I
Acct 1
Acct 2
If we have a total of 1500 to split up between 2 accounts, we put x amount of money into one and then have 1500-x left to put into the other. We will fill those in along with the interest rates in decimal form and the time of 1 year:
P * r * t = I
Acct 1 x .04 1
Acct 2 1500-x .05 1
Looking at the formula we are told that Prt = I, so we will multiply P times r times t and fill in the I column:
P * r * t - I
Acct 1 x .04 1 .04x
Acct 2 1500-x .05 1 .05(1500-x)
The total Interest earned by the addition of the interest earned from both accounts is 69.50. So we add the interest column together and set it equal to 69.50:
.04x + .05(1500 - x) = 69.50 and
.04x + 75 - .05x = 69.50 and
-.01x = -5.5 so
x = 550
That's how much money is in the account earning 4% interest.
There are infinitely many solutions to this problem (which is why it asks what could those numbers be), so you just have to make one up!
Start with the first sentence.
x + y + z = 6.0
Now one of those numbers has to be less than 1. I'll choose x. And I'll choose a random number, say, 0.7.
0.7 + y + z = 6.0
Now I'll subtract 0.7 from both sides to see what y and z have to add up to.
0.7 + y + z - 0.7 = 6.0 - 0.7
y + z = 5.3
Now I'll choose a random number for y that's less than 5.3.
2.6 + z = 5.3
And subtract 2.6 from both sides to find z.
2.6 + z - 2.6 = 5.3 - 2.6
z = 2.7
And now we have our numbers!
x = <u>0.7</u>
y = <u>2.6</u>
z = <u>2.7</u>
Find the area of trapezoid.
1/2(6+10)(3) = 24
Now multiply 24 by $4 to find the total cost.
24 * 4 = 96
So the total cost is $96
Hope this helps :)
What part do you not understand?