It form a right triangle
legnth of ladder is hypotonuse
bottom of ladder from wall distance is one leg
distance up wall is other leg
a^2+b^2=c^2
c=hypotonuse and a and b are legs
4^2+b^2=20^2
16+b^2=400
minus 16 both sides
b^2=384
sqrt both sides
b=8√6 ft
aprox
b=19.59ft from ground
Answer:
Step-by-step explanation:
Using a discrete probability distribution, it is found that:
a) There is a 0.3 = 30% probability that he will mow exactly 2 lawns on a randomly selected day.
b) There is a 0.8 = 80% probability that he will mow at least 1 lawn on a randomly selected day.
c) The expected value is of 1.3 lawns mowed on a randomly selected day.
<h3>What is the discrete probability distribution?</h3>
Researching the problem on the internet, it is found that the distribution for the number of lawns mowed on a randomly selected dayis given by:
Item a:
P(X = 2) = 0.3, hence, there is a 0.3 = 30% probability that he will mow exactly 2 lawns on a randomly selected day.
Item b:

There is a 0.8 = 80% probability that he will mow at least 1 lawn on a randomly selected day.
Item c:
The expected value of a discrete distribution is given by the <u>sum of each value multiplied by it's respective probability</u>, hence:
E(X) = 0(0.2) + 1(0.4) + 2(0.3) + 3(0.1) = 1.3.
The expected value is of 1.3 lawns mowed on a randomly selected day.
More can be learned about discrete probability distributions at brainly.com/question/24855677
Answer:
Step-by-step explanation:
4ox-16=4[10x-4]this is because 4 is the common factor in both 40and 16
16x-24x-4±12=4[4x-6x-1±3]
-8x-8=8[-1-1]
54 divide 3*3=54 is the answer