Answer:
Step-by-step explanation:
The equation which can be used to find the number of quarters and nickels is; n + q = 84, 0.05n + 0.25q = 17.80.
<h3>Quarters and nickels</h3>
- Total coins = 84
- Total value = $17.80
let
- Number of quarters = q
- Number of nickels = n
n + q = 84
0.05n + 0.25q = 17.80
From equation (1)
n = 84 - q
Substitute into (2)
0.05n + 0.25q = 17.80
0.05(84 - q) + 0.25q = 17.80
4.2 - 0.05q + 0.25q = 17.80
- 0.05q + 0.25q = 17.80 - 4.2
0.20q = 13.60
q = 13.60 / 0.20
q = 68
Substitute q = 68 into
n + q = 84
n + 68 = 84
n = 84 - 68
n = 16
Therefore, the number of quarters and nickels are 68 and 16 respectively.
Learn more about quarters and nickels:
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Olga worked 37.5 hours last week and earned $12.50 an hour.
[ h = the number of hours y = total earnings ]
12.50h = y
12.50(37.5) = y
468.75 = y
She earned $468.75 last week
If she gets a $2.50 per hour raise:
12.50 + 2.50 = 15.00
She gets $15 per hour.
How many hours will she have to work to make $468.75?
15h = 468.75 Divide 15 on both sides to get "h" by itself
h = 31.25
She needs to work 31.25 hours
The answer is........4w+10-5r
Part A
Correlation coefficient: -.99
This tells us that as time goes on (value of x increases) the area of the puddle goes down (value of y decreases)
Part B
y₂ - y₁
------- = slope
x₂ - x₁
9 - 15
--------
5 - 8
-6/-3 = 2
So the slope equals -2, regardless of the fact that we got 2 as an answer there, we know that it is a negative slope
Part C
The data represents causation because an increase in the value of x results in a decrease in the value of y, this shows an example of direct causation between x and y.
