Answer: (1) 7:5 (2) 2:9 (3) 3:4
<u>Step-by-step explanation:</u>
![\frac{a}{5} = \frac{b}{7}](https://tex.z-dn.net/?f=%5Cfrac%7Ba%7D%7B5%7D%20%3D%20%5Cfrac%7Bb%7D%7B7%7D)
cross multiply to get: 7a = 5b
ratio = 7:5
*************************************
2a = 9b
ratio = 2:9
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6a - 3b = 5b
<u> +3b</u> <u>+3b </u>
6a = 8b
<u>÷2 </u> <u> ÷2 </u>
3a = 4b
ratio = 3:4
I think -0.5
3-5= -2
-2x.25= -0.5
Answer: Option B
Step-by-step explanation:
We can use the binomial formula to solve this problem.
![P(X) = \frac{n!}{x!(n-x)!}*p^x(1-p)^{n-x}](https://tex.z-dn.net/?f=P%28X%29%20%3D%20%5Cfrac%7Bn%21%7D%7Bx%21%28n-x%29%21%7D%2Ap%5Ex%281-p%29%5E%7Bn-x%7D)
Where p is the probability of success, n is the sample size and x is the number of successes expected.
Note that in this case
(probability of an adult passing the fitness test)
![n = 100](https://tex.z-dn.net/?f=n%20%3D%20100)
![x = 17](https://tex.z-dn.net/?f=x%20%3D%2017)
Then we calculate the probability
![P(X=17) = \frac{100!}{17!(100-17)!}*0.1^{17}(1-0.1)^{100-17}](https://tex.z-dn.net/?f=P%28X%3D17%29%20%3D%20%5Cfrac%7B100%21%7D%7B17%21%28100-17%29%21%7D%2A0.1%5E%7B17%7D%281-0.1%29%5E%7B100-17%7D)
![P=0.0106](https://tex.z-dn.net/?f=P%3D0.0106)