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
In slope intercept, the equation is y = -x - 4
<span>C = 45 + 18 + 27 - 21 - 93
C = -24
Let's use the variable C to represent the change in the balance in Cody's checking account. The easiest way to make the expression is to simply apply the additions and subtractions directly. So let's start with C
C
"Cody made deposits of $45, $18, and $27 into his checking account."
C = 45 + 18 + 27
"He then wrote checks for $21 and $93."
C = 45 + 18 + 27 - 21 - 93
So the expression to represent the change to Cody's checking account is
C = 45 + 18 + 27 - 21 - 93
Now to simplify it. All you need to do is combine terms together. How far you go is up to you. So let's do it.
C = 45 + 18 + 27 - 21 - 93
I'll add together all the deposits.
C = (45 + 18 + 27) - 21 - 93
C = 90 - 21 - 93
And I'll combine the checks.
C = 90 - 114
So now you can tell at a glance that Cody deposited $90 and wrote checks for $114. But we can make it simpler and combine those as well. So
C = -24
And this tells you that Cody's checking account balance is now $24 lower than it was before he started making deposits and writing checks.</span>
173+32=205 , so 205 times 5 would equal 1,025 . so the answer would be 1,025 .
Answer:
9x² + 33x + 28
Step-by-step explanation:
