Answer:
Step-by-step explanation:
I say A
Answer:
7500
Step-by-step explanation:
34500-27000=7500
Answer:
The true statement is: In step 3 she needed to subtract c rather than divide.
Step-by-step explanation:
Lets solve our equation
step by step.
Step 1. Since 3 is the denominator of the right hand side, we need to multiply both sides of the equation by 3:
![3s=\frac{3(a+b+c)}{3}](https://tex.z-dn.net/?f=3s%3D%5Cfrac%7B3%28a%2Bb%2Bc%29%7D%7B3%7D)
Now we can cancel the 3 in the numerator and the 3 in the denominator to get
![3s=a+b+c](https://tex.z-dn.net/?f=3s%3Da%2Bb%2Bc)
As you can see, the first statement is false
Step 2. Since we want to isolate the variable
, we need to subtract b from both sides of the equation:
![3s=a+b+c](https://tex.z-dn.net/?f=3s%3Da%2Bb%2Bc)
![3s-b=a+b+c-b](https://tex.z-dn.net/?f=3s-b%3Da%2Bb%2Bc-b)
![3s-b=a+c](https://tex.z-dn.net/?f=3s-b%3Da%2Bc)
The second statement is also false
Step 3. The last thing we to do to isolate
(and solve for it) is subtract c from both sides of the equation:
![3s-b-c=a+c-c](https://tex.z-dn.net/?f=3s-b-c%3Da%2Bc-c)
![3s-b-c=a](https://tex.z-dn.net/?f=3s-b-c%3Da)
![a=3s-b-c](https://tex.z-dn.net/?f=a%3D3s-b-c)
Therefore, the third statement is true: In step 3 she needed to subtract c rather than divide.
Given:
From 1:00 pm to 3:30 pm the room temperature had dropped from 82F to 72F.
To find:
The average rate of change of temperature in this room over the period.
Solution:
Time between 1:00 pm to 3:30 pm is 2 hr 30 minutes, i.e., 2.5 hours.
So, change in time is 2.5 hours.
Room temperature had dropped from 82F to 72F.
Change in temperature = 72 F - 82 F
= -10 F
We know that, average rate of change of temperature in this room over the period is
![m=\dfrac{\text{Change in temperature}}{\text{Change in time}}](https://tex.z-dn.net/?f=m%3D%5Cdfrac%7B%5Ctext%7BChange%20in%20temperature%7D%7D%7B%5Ctext%7BChange%20in%20time%7D%7D)
![m=\dfrac{-10}{2.5}](https://tex.z-dn.net/?f=m%3D%5Cdfrac%7B-10%7D%7B2.5%7D)
![m=-4](https://tex.z-dn.net/?f=m%3D-4)
Therefore, the average rate of change of temperature in this room over the period is -4. It means the temperature is decreasing 4 F per hour.
37 440 US$ hope this helps you