You're going to want to combine like terms first off, so 2x+3x=5x. Then you have 5x+7=-41. Now you subtract 7 from both sides, and basically undo that function so you have 5x=-48. Then you do the opposite of multiplying 5, so you divide five from both sides and get -9.6. So x=-9.6. Is that what you wanted? Because if not, ignore this.
This is a simultaneous question.
To solve this, we have to make up 2 equations based on the info provided like so:
electricity = e
gas = g
600e + 100g = $412 ——(1)
400e + 150g = $293 ——(2)
In this case, it’ll be easier to use the elimination method where you eliminate a variable so you can calculate only one.
Here, we will be eliminating e so we can get the cost of gas.
To do this we need to get both equation’s e to 600, so we have to multiply equation 2 by 1.5:
(2) x 1.5:
400e + 150g = $293
600e + 225g = $439.50 ——(3)
Now we eliminate e by subtracting equation 1 from equation 3:
(3) - (1):
600e + 225g - 600e - 100g = $439.50 -$412
125g = $27.50
g = $0.22.
Therefore one unit of gas costs $0.22.
Hope it helps and have a good day ahead :D
Answer:
Step-by-step explanation:
Mark got 54 out of 66 correct in his test.
We need to find what fraction of the marks did he get correct,
Total number of questions = 66
Total number of correct answers = 54
Answer:
a) The third quartile Q₃ = 56.45
b) Variance 
Step-by-step explanation:
Given that :
= 30.8
Median 
= 48.5
Mean = 42
a) The mean is less than median; thus the expression showing the coefficient of skewness is given by the formula :
Divide both sides by 1.38
b) The objective here is to determine the approximate value of the variance;
Using the relation
Variance = 
Answer:
See below. The series converges.
Step-by-step explanation:
