Answer:
We simplify the equation to the form, which is simple to understand
5x+15=4x-12
We move all terms containing x to the left and all other terms to the right.
+5x-4x=-12-15
We simplify left and right side of the equation.
+1x=-27
then divide both sides of the equation by 1 to get x.
x=-27
Answer: MATH
Step-by-step explanation:
(a) Average time to get to school
Average time (minutes) = Summation of the two means = mean time to walk to bus stop + mean time for the bust to get to school = 8+20 = 28 minutes
(b) Standard deviation of the whole trip to school
Standard deviation for the whole trip = Sqrt (Summation of variances)
Variance = Standard deviation ^2
Therefore,
Standard deviation for the whole trip = Sqrt (2^2+4^2) = Sqrt (20) = 4.47 minutes
(c) Probability that it will take more than 30 minutes to get to school
P(x>30) = 1-P(x=30)
Z(x=30) = (mean-30)/SD = (28-30)/4.47 ≈ -0.45
Now, P(x=30) = P(Z=-0.45) = 0.3264
Therefore,
P(X>30) = 1-P(X=30) = 1-0.3264 = 0.6736 = 67.36%
With actual average time to walk to the bus stop being 10 minutes;
(d) Average time to get to school
Actual average time to get to school = 10+20 = 30 minutes
(e) Standard deviation to get to school
Actual standard deviation = Previous standard deviation = 4.47 minutes. This is due to the fact that there are no changes with individual standard deviations.
(f) Probability that it will take more than 30 minutes to get to school
Z(x=30) = (mean - 30)/Sd = (30-30)/4.47 = 0/4.47 = 0
From Z table, P(x=30) = 0.5
And therefore, P(x>30) = 1- P(X=30) = 1- P(Z=0.0) = 1-0.5 = 0.5 = 50%
Answer:
regular 4 is correct
Step-by-step explanation:
Answer: the group rented 11 Person tubes and 4 cooler tubes
Step-by-step explanation:
There are two types of tubes, Person tube and cooler tube.
Let P represent number of Person tubes that the group rented.
Let C represent number of Cooler tubes that the group rented.
The group spends $270 to rent a total of 15 tubes and Person tube $20 Cooler tube $12.50. Two linear equations can be derived from the above information
P + C = 15 - - - - - - - 1
20P + 12.5C = 270 - - - -- - - 2
Substituting P = 15 - C into equation 2,
It becomes
20(15-C) + 12.5C = 270
300 - 20C + 12.5C = 270
- 20C + 12.5C = 270 -300
7.5C = - 30
C = 30/7.5 = 4
P = 15 - C
P = 15 - 4 = 11
