Answer:
look at explanation
Step-by-step explanation:
To solve all of these questions you just need to scale. While scaling you can divide or multiply.
1.
(divide by 4 to get unit rate)
unit rate = 
2. If it takes one hour to travel 40 miles, then we don't have to scale or anything. We know
, the answer is...
"It'll only take one hour to travel 40 miles. This is correct because the unit rate is
. "
3. Knowing that the constant speed of the plane is
, we can scale then add half of the unit rate to get our answer.
x 3 =
800 x 3 = 2400
then add half of unit rate which is
= 400
so, our answer is 
4.
<--- ( divided by 2)
( multiplied x 2.5) ---> 
To get an easier way to find the answer, if possible you can scale back farther than the 1 hour mark.
Elmer would take 2 and a half hours to ride 15 km.
5. The boys speed is
. All we need to do is divide by 2.
= 4
Answer:
A) 2.6 mm Hg
Step-by-step explanation:
Margin of error = critical value × standard error
ME = CV × SE
n > 30, so we can approximate CV with a normal distribution. At P = 94%, CV = 1.88.
SE = σ / √n
SE = 13.5 / √92
SE = 1.41
So the margin of error is:
ME = 1.88 × 1.41
ME = 2.6
6/7Y - 18/28 =-15/14
First, let's get a common denominator
24/28Y - 18/28 =-30/28
Move your terms to isolate Y
24/28Y=-12/28
Multiply by 28 on both sides
24/Y=-12
Times both sides by Y, then divide by -12
24/-12=Y
Simplify
-2=Y
I hope this Helps!