Answer:
a) 68.2%
b) 31.8%
c) 2.3%
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = 530
Standard Deviation, σ = 119
We are given that the distribution of math scores is a bell shaped distribution that is a normal distribution.
Formula:

a) P(test scores is between 411 and 649)

b) P(scores is less than 411 or greater than 649)

c) P(score greater than 768)
P(x > 768)


Calculation the value from standard normal z table, we have,

Since if he gets the driveway done in 20 minutes he gets 1/20th of the driveway done in 1 minute (if x=20 then x/20=1 by dividing both sides by 20) and if his brother gets 1/12th of the driveway done in one minute, then if t represents the time it takes to shovel the driveway, t/20+t/12=1 driveway shoveled as 1/20+1/12=amount they can do in 1 minute, so t/20+t/12 is how much they can do in t minutes. Multiplying both sides by 20*12=240, we get 12t+20t=32t=240. Dividing both sides by 32, we get 240/32=7.5 minutes to shovel the driveway.
The second angle would be 140⁰. When two angles are supplementary, they add up to 180⁰.
180⁰-40⁰=140⁰
Answer:
m∠6 = 116°
Step-by-step explanation:
<u>first find x:</u>
7x - 17 = 2x + 78
subtract 2x from both sides: 5x - 17 = 78
add 17 to both sides: 5x = 95
divide by 5: x = 19
<u>plug x into 7x - 17</u>
7(19) - 17 = 116
∠6 and 7x - 17 are vertical angles and therefore congruent, so m∠6 also = 116°
Answer:
your answer might be 3
Step-by-step explanation: