Answer:
6 hours.
Step-by-step explanation:
The formula sort of has to be invented.
Al
rate = 1 shed / 2 hours
Tom
rate = 1 shed / x hours.
Together.
rate = 1 shed / 1.5 hours.
Equation
1 shed / 2 hours + 1 shed / x hours = 1 shed / 1.5 hours.
1/2 + 1/x = 1/1.5 Put the fractions over a common denominator.
(x + 2) / 2x = 1 / 1.5 Cross Multiply
1.5(x + 2) = 2x Remove the Brackets.
1.5x + 3 = 2x Subtract 1.5x from both sides
3 = 2x - 1.5x
3 = 0.5x Multiply both sides by 2
6 = x
It would take Al 6 hours to do the shed on his own.
For this type of question, we have to take out the percentage of each candidate:
For Arthur
85 from 95
Convert 95 to 100
That means that we have to add 5, do the same thing with 85. Add 5 to 85 and you get 90. That means Arthur got 90% For Miguel 64 from 76. Covert 76 to 100. That means we have to add 24. Do the same thing with 64. Add 24 + 64. It equals 88% Miguel got 88%
Answer:
As the sample size increases, the variability decreases.
Step-by-step explanation:
Variability is the measure of actual entries from mean. The less the deviations the less would be the variance.
For a sample of size n, we have by central limit theorem the mean of sample follows a normal distribution for random samples of large size.
X bar will have std deviation as
where s is the square root of variance of sample
Thus we find the variability denoted by std deviation is inversely proportion of square root of sample size.
Hence as sample size increases, std error decreases.
As the sample size increases, the variability decreases.
Answer:
17
Step-by-step explanation:
A straight line equals 180 degrees. The box on the left indicates a right angle which equals 90 degress. The 90 and 39 degress are given, and when added together that equals 129 degrees. If the total line is 180 degress, you would subtract the 129 degrees from it to get 51. This means that 3(x)= 51. You do 51/3 which equals 17, or x=17.
X= 13 would be the answer