SOLUTION: 1.find all real values of 'w' for which the statement C(w+1,2)=9•C(w,1) is true. 2. while shooting arrows, William can hit an apple 9 out of 10 times. what is the probability t

Algebra.Com
Question 203977: 1.find all real values of 'w' for which the statement
C(w+1,2)=9•C(w,1) is true.
2. while shooting arrows, William can hit an apple 9 out of 10 times. what is the probability that he will hit it exactly 4 out of the next 7 times.
*both of them were really hard for me to figure out. I appreciate your help.

Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
1.find all real values of 'w' for which the statement
C(w+1,2)=9•C(w,1) is true.
--------------------
(w+1)!/[w-1)!2!] = 9w
---
Simplify:
[(w+1)w]/2 = 9w
w^2+w-18w = 0
w^2-17w = 0
w(w-17) = 0
Positive solution:
w = 17
-----------------------------------------------

2. while shooting arrows, William can hit an apple 9 out of 10 times. what is the probability that he will hit it exactly 4 out of the next 7 times.
P(x=4) = 7C4(0.9)^4(0.1)^3 = 0.02296..
============================================
Cheers,
Stan H.

RELATED QUESTIONS

While shooting arrows, William tell can hit an apple 9 out of 10 time.What is the... (answered by ewatrrr)
While shooting arrows, William Tell can hit an apple 9 out of 10 times. What is the... (answered by edjones)
How do I find all the values of w satisfying the equation? 6-5/w+2=-4/w-1 (answered by checkley71)
Half the perimeter of a garden is 18 feet. The garden is 8 feet longer than it is wide.... (answered by Earlsdon)
If 1 and w are 2 of the 5 roots of (w)^5 = 1, then prove the following: a) (w)^2,... (answered by Edwin McCravy,mccravyedwin)
3(w+1)-5=2(W-1)+w What's the correct answer to this problem? (a)-2 (b)all real Numbers... (answered by LinnW)
Perform the indicated operations and simplify (w-1/w-9)-(w+1/w+9)+(w-153/w^2-81)... (answered by stanbon)
A baker is creating a recipe and must include pleces of recipes from both websites and... (answered by josgarithmetic)
1/(a w) 1/(b w) 1/(c w) 1/(d w)=2w^2 and 1/(a w^2) 1/(b w^2) 1/( c w^2) 1/(d (answered by ikleyn)