The angle of 2 is 150 degrees
Answer:
The three numbers are 7 8 and 9
Step-by-step explanation:
Givens
- Let the first number be n - 1
- Let the second number be n
- Let the third number = n + 1
Equation
(n - 1)(n)(n + 1) - (n-1 + n + n+1) = 480
Solution
Multiply (n - 1) and (n + 1) = (n - 1)*(n + 1) = n^2 - 1
Multiply the second integer by the result of the first and third: n (n^2 - 1)
Add the three integers together: (x - 1) + (n - 1) + n = 3n Combine these 2 steps
n(n^2 - 1) - 3n = 480 Remove the brackets
n^3 - n - 3n = 480
n^3 - 4n = 480
n^3 - 4n - 480 = 0
Graph
The graph shows that the intercept point is n =8. This is the only way I can see to solve this cubic. There are no other real roots.
Answer
n - 1 = 7
n = 8
n + 1 = 9
Check
Product 7*8*9 = 504
Sum = 7 + 8 + 9 = 24
504 - 24 = 480 Which checks.
Complete question :
The 100m dah times in the girl's track meet were normally distributed with a mean of 13 seconds and a standard deviation of 0.3 seconds.
Lana finished the race in 13.2 seconds . If 84 other girls ran in the event, approximately how many runners did she beat?
Answer:
21 runners
Step-by-step explanation:
Mean, μ = 13 seconds
Standard deviation, σ = 0.3
Lana's race time = 13.2
We find the proportion of runners who had race time above 13.2 ;
Proportion of who had race tune above 13.2
P(x > 13.2)
Obtain the Zscore
Zscore = (x - μ) / σ
Z = (13.2 - 13) / 0.3
Zscore = 0.2 / 0.3 = 0.6667
P(Z > 0.6667) = 0.25239 (Z probability calculator)
This is about 0.25239 * 100 = 25.24% = 25% (nearest percent)
Hence, Number of runners Lana beat = 25% of total runners ;
0.25 * 84 = 21
Hence, Lana beat about 21 runners
I want to say it’s the second one