Answer:
y+30
Step-by-step explanation:
the sum of the numbers is 15y
the new sum after increase each number by 30 is 15y+450
the new mean 15y+450/15
= y+30
Ok, so after you do -8a+5a, you also have to do 6 -35, getting the equation
-29-3a
5.3 minutes.
First, let's calculate the volume of the tank. That will be the area of the base multiplied by it's length. And since it's base is a circle, the area is pi*r^2. So:
V = l*pi*r^2
V = 3.5 * pi * (2.2/2)^2
V = 3.5 * pi * (1.1)^2
V = 3.5 * pi * 1.21
V = 4.235 * pi
V = 13.30464489
So the tank has a volume of about 13.3 ft^3. Now simply divide that volume
by the rate of incoming fluid. So
13.3 / 2.5 = 5.32
Rounding to 2 significant figures gives a time of 5.3 minutes.
Answer: c. 
Step-by-step explanation:
As per given , we have
Total number of residents injured from roller-skating =1,800
Total number of deaths from roller-skating = 90
Formula for Mortality rate : 
Then, the proportional mortality ratio (%) due to roller-skating was
=
= 5%
Hence, the correct answer is c.
First you find how much weight it lost
500 - 350 = 150
Then, to find the mean change you divide the weight lost by the number of months
150 : 6 = 25
25 is the monthly change
