Answer:
9 is the number
Step-by-step explanation:
Let's call this number x
The equation is:
30+2x=48
subtract 30 from both sides and you get
2x=18
divide 2 from both sides and you get
x=9
Therefore, 30+2(9)=48
<h3>Answer: Commutative Property (choice C)</h3>
===================================================
Explanation:
Here are all of the justifications for each step
- Step 1. None needed. This is the original expression
- Step 2. Distributive property
- Step 3. Multiply (the 3 and 5 multiply to 15)
- Step 4. Commutative property. Specifically, this is the commutative property of addition which allows us to add any two numbers in any order we want. In this case, the -15 and 4x terms swap places.
- Step 5. Associative property. The parenthesis group the first two terms away from the third term.
- Step 6. Combine like terms. Both 3x and 4x have an x only so they are like terms that combine to 7x. You can think of it as 3+4 = 7, then you just tack an x onto everything to get 3x+4x = 7x.
Answer:
a.) f(x) = 
where 90 < x < 120
b.) 
c.)
d.) 
Step-by-step explanation:
Let
X be a uniform random variable that denotes the actual charging time of battery.
Given that, the actual recharging time required is uniformly distributed between 90 and 120 minutes.
⇒X ≈ ∪ ( 90, 120 )
a.)
Probability density function , f (x) = 
where 90 < x < 120
b.)
P(x < 110) = 
= ![\frac{1}{30}[x]\limits^{110}_{90} = \frac{1}{30} [ 110 - 90 ] = \frac{1}{30} [ 20] = \frac{2}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B30%7D%5Bx%5D%5Climits%5E%7B110%7D_%7B90%7D%20%20%3D%20%5Cfrac%7B1%7D%7B30%7D%20%5B%20110%20-%2090%20%5D%20%3D%20%5Cfrac%7B1%7D%7B30%7D%20%5B%2020%5D%20%3D%20%5Cfrac%7B2%7D%7B3%7D)
c.)
P(x > 100 ) = 
= ![\frac{1}{30}[x]\limits^{120}_{100} = \frac{1}{30} [ 120 - 100 ] = \frac{1}{30} [ 20] = \frac{2}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B30%7D%5Bx%5D%5Climits%5E%7B120%7D_%7B100%7D%20%20%3D%20%5Cfrac%7B1%7D%7B30%7D%20%5B%20120%20-%20100%20%5D%20%3D%20%5Cfrac%7B1%7D%7B30%7D%20%5B%2020%5D%20%3D%20%5Cfrac%7B2%7D%7B3%7D)
d.)
P(95 < x< 110) = 
= ![\frac{1}{30}[x]\limits^{110}_{95} = \frac{1}{30} [ 110 - 95 ] = \frac{1}{30} [ 15] = \frac{1}{2}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B30%7D%5Bx%5D%5Climits%5E%7B110%7D_%7B95%7D%20%20%3D%20%5Cfrac%7B1%7D%7B30%7D%20%5B%20110%20-%2095%20%5D%20%3D%20%5Cfrac%7B1%7D%7B30%7D%20%5B%2015%5D%20%3D%20%5Cfrac%7B1%7D%7B2%7D)
Answer:
The elevator stops on the 19th floor.
Step-by-step explanation:
On the 16th floor, goes up 12 floors:
16 + 12 = 28
On the 28th floor, goes down 7 floors:
28 - 7 = 21
On the 21st floor, does up 3 floors:
21 + 3 = 24
On the 24th floor, goes down 5 floors:
24 - 5 = 19
