Answer:
x=16
Step-by-step explanation:
Actually this is trig I believe.
cos60=8/x
x=8/cos60=16
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
There is an infinite number of chords in a circle
Here it is given that AB || CD
< EIA = <GJB
Now
∠EIA ≅ ∠IKC and ∠GJB is ≅ ∠ JLD (Corresponding angles)
∠EIA ≅ ∠GJB then ∠IKC ≅ ∠ JLD (Substitution Property of Congruency)
∠IKL + ∠IKC 180° and ∠DLH + ∠JLD =180° (Linear Pair Theorem)
So
m∠IKL + m∠IKC = 180° ....(1)
But ∠IKC ≅ ∠JLD
m∠IKC = m∠JLD (SUBTRACTION PROPERTY OF CONGRUENCY)
So we have
m∠IKL + m∠JLD = 180°
∠IKL and ∠JLD are supplementary angles.
But ∠DLH and ∠JLD are supplementary angles.
∠IKL ≅ ∠DLH (CONGRUENT SUPPLEMENTS THEOREM)
The correct answer is A. Not only does $250 a week equal $1000 a month but the commission is also higher.
first job: $250wk = $1000 Month + .045 commission
= $12000 year + .045 commission
second job = $1800 Month + .03 commission
= $21600 year + .03 commission
commission based on sales of $1,000,000
1,000,000 times .045 = $45000
1,000,000 times .030 = $30000
FIRST JOB: $12,000 + $45,000 = $57,000
SECOND JOB: $21,600 + $30,000 = $51,600
The answer is definitely A.