Answer:
10
Step-by-step explanation:
4x+8+3x+12=90
x=10
this is the solution hope it's helpful
You only need to consider the situations where 10 or 11 of the babies are girls, then subtract those probabilities from 1. This will give probability that any other number up to 9 of the babies are girls.
Use binomial theorem.
n = 11
k = 10,11
p = 1/2
I only did the first part but maybe later I will solve the rest too. If there are any errors but tell me so I can update the pic.
Drawing a diagram of a triangle may be helpful. The hypotenuse is irrelevant, but the vertical leg and the horizontal leg are useful. Since we know the engineer is looking up at a 45 degree angle from a distance of 200 feet, we can label the vertical leg the "opposite", since it is on the opposite side of the angle we are given. The horizontal leg then becomes the "adjacent". You can then use trigonometry to solve for the opposite.
The options are:
sin(theta)= opposite/hypotenuse
cos(theta)= adjacent/hypotenuse
tan(theta)= opposite/adjacent
Since we don't care about the hypotenuse, the last equation is the one to use. The angle we are given can be substituted in for theta:
tan(45)= x/200
1.61977519= x/200
x= 323.955038 feet
