Each question has four choices, then the probability to guess a correct answer is

and the probability to select incorrect choice is

.
You have a 5-question multiple-choice test, then n=5. The <span>probability that you will guess exactly three out of five questions correctly is </span>
<span /><span>
</span><span>

</span>

.
<span />
Answer:
4x+y add like terms ... -5+9=4 and -y(or -1)+2y=y
4,000,000 and 20,000,000 miles²
let x be the area of one desert then 5x is the area of the other
sum = x + 5x = 24,000,000
6x = 24,000,000
divide both sides by 6
x = 4,000,000
one desert is 4,000,000 miles²
and the other is (5 × 4,000,000)= 20,000,000 miles²
Answer:
John is 17,
Susan is 14,
and Khalid is 9.
Step-by-step explanation:
a = John's age
b = Susan's age
c = Khalid's age
Let's set our rules from the given information.
a = b + 3
c = b - 5
a + b + c = 40
Now, we can solve for b through substitution.
(b + 3) + b + (b - 5) = 40
3b - 2 = 40
3b = 42
b = 14
So, now that we have Susan's age, we can follow the rules and see if it holds.
17 + 14 + 9 = 40 Viola!
A^2 + b^2 = c^2
(500)^2 + (1200)^2 = c^2
1,690,000 = c^2
take the square root of 1,690,000
Answer is 1,300 feet