Given:
The rate of interest on three accounts are 7%, 8%, 9%.
She has twice as much money invested at 8% as she does in 7%.
She has three times as much at 9% as she has at 7%.
Total interest for the year is $150.
To find:
Amount invested on each rate.
Solution:
Let x be the amount invested at 7%. Then,
The amount invested at 8% = 2x
The amount invested at 9% = 3x
Total interest for the year is $150.

Multiply both sides by 100.


Divide both sides by 50.


The amount invested at 7% is
.
The amount invested at 8% is

The amount invested at 9% is

Thus, the stockbroker invested $300 at 7%, $600 at 8%, and $900 at 9%.
The answer is actually 80 degrees, I just took the test.
Answer:
-89
Step-by-step explanation:
The first term of the sequence is a1 = -12.
The common difference between terms is ...
d = -13 -(-12) = -1
The generic term is given by ...
an = a1 +d(n -1)
Then the 78th term is ...
a78 = -12 +(-1)(78 -1) = -12 -77
a78 = -89
Answer:

Step-by-step explanation:
For this case we want to find this probability:

Because they want the area to the left of the value. We need to remember that the normal standard distribution have a mean of 0 and a deviation of 1.
We can use the following excel code: =NORM.DIST(-1.55,0,1,TRUE)
And we got:

The other possibility is use the normal standard table and we got a similar result.
1. A = ¹/₂bh
A = ¹/₂(25)(4)
A = ¹/₂(100)
A = 50 yd²
3. A = ¹/₂bh
A = ¹/₂(3)(1)
A = ¹/₂(3)
A = 1¹/₂ cm²