Answer:
a+b=b+a
Step-by-step explanation:
so 7+4=12 and 4+7=12 so addition is commutative
Answer:
The mean is 41
Step-by-step explanation:
Here , we are interested in finding the mean.
Firstly, let the standard deviation be x and the mean be y.
We are told that 51 is 2 standard deviations above the mean. What this mean is that if we subtract 2 standard deviations from 51, we will arrive at the mean.
Mathematically;
51 - 2(x) = y
y + 2x = 51 •••••••••(i)
We are also told that 36 is one standard deviation below the mean. What this mean is that if we subtract one standard deviation from the mean, we will have 36
Mathematically, that would be;
y-36 = x •••••••(ii)
Substitute ii into i directly;
We have
y + 2(y-36) = 51
y + 2y -72 = 51
3y -72 = 51
3y = 51 + 72
3y = 123
y = 123/3
y = 41
5y=3y+6
2y=6
y=3
It would be the 4th bubble
She needs to purchase a cover to protect the hot tub of an area of 38.5 square feet.
<h3>What is a circle?</h3>
It is a locus of a point drawn at an equidistant from the center. The distance from the center to the circumference is called the radius of the circle.
Claire has a hot tub with a diameter of 7 feet. She wants to purchase a cover to protect the hot tub.
The area of the circle is given by

We have d = 7 ft, then the area of the circle will be

More about the circle link is given below.
brainly.com/question/11833983