Answer:
1. a. 2,000
2. b. 10 years
3. a. 6.72937
4. d. 9%
Step-by-step explanation:
1. If 58% are boys, the percentage of girls is:
= 100 - 58
= 42%
That means 840 is 42% of the students in class. The students in class are therefore:
= 840 / 42%
= 2,000 students
2. If Birr 300 is invested at 6% per year, the amount in interest it earns per year is:
= 300 * 6%
= Birr 18
To get to Birr 180, it would take:
= 180/18
= 10 years
3. When a number is in percentage that means that it is a fraction with the denominator being 100. The number is decimal will therefore be it divided by 100:
= 672.937/100
= 6.72937
4. The investment accrued Birr 12 out of Birr 400 in 4 months. This means that it increased by:
= 12/400
= 3%
A year can be divided into three by 4 months. This means that the yearly rate is therefore:
= 3% * 3
= 9%
Evaluate 3x for x = −2, x = 1, and x = 3. Question 18 options: A) 1∕3, 0, 9 B) 1∕9, 3, 27 C) 9, 3, 27 D) 1∕9, 9, 27
icang [17]
Answer: B) 1/9, 3, 27
Step-by-step explanation:
Here, we need to evaluate
for 
So, we substitute values of x in the given function.
At x= -2, we have
![3^{-2}=\dfrac{1}{3^2}=\dfrac{1}{9}\ \ \ [\because\ a^{-n}=\dfrac{1}{a^n}]](https://tex.z-dn.net/?f=3%5E%7B-2%7D%3D%5Cdfrac%7B1%7D%7B3%5E2%7D%3D%5Cdfrac%7B1%7D%7B9%7D%5C%20%5C%20%5C%20%5B%5Cbecause%5C%20a%5E%7B-n%7D%3D%5Cdfrac%7B1%7D%7Ba%5En%7D%5D)
At x= 1, we have

At x= 3

So, the values of
for
Thus, the correct answer is B) 1/9, 3, 27
Answer:
Substitution property of equality
Step-by-step explanation:
Given
and 
Then

Required
State the property
From the list of options, (d) answers the question.
This is so because:
Substitution property of equality states that
If
then 
In other words, both can replace one another.
So if
, then 2y + 1 can be substituted for x in
So:
becomes

<em>Hence, it is substitution property of equality</em>
On the 21st day; the 7th day of the back medication and the 3rd day of the asthma medication.
Answer:
xˆ2+10x+9
Step-by-step explanation:
first, multiply x by x and by 1, that would be (xˆ2 and x), then multiply 9 by x and 1, that would be( 9x and 9), add the two parenthesis, and it totals out to xˆ2+10x+9