Answer:
a. P(x>20)=0.19
b. P(x≥6)=0.72
c. P(x≤20)=0.81
d. A and C
Step-by-step explanation:
We know that:
1) the probability that a student makes fewer than 6 mistakes is 0.28
2) The probaiblity that a student makes between 6 to 20 mistakes is 0.53.
We will express the proabilibities in function of the information we have.
a. Probability that a student makes more than 20 mistakes.
b. Probability that the student make 6 or more mistakes
c. Probability that a student makes 20 mistakes at most
d. A and C, because A takes a event of more than 20 mistakes and C takes the event of 20 or less mistakes. Both events cover a probability of 1.
Answer:
3 cube root of 15
Step-by-step explanation:
theres your simple radical form
Answer:
7 : 5
Step-by-step explanation:
let the age of the younger be x , then the older is x + 18, thus
x + x + 18 = 108, that is
2x + 18 = 108 ( subtract 18 from both sides )
2x = 90 ( divide both sides by 2 )
x = 45
Thus younger is 45 and older is 45 + 18 = 63
ratio older : younger = 63 : 45 = 7 : 5
Answer:
Length = 10.435 inches
Step-by-step explanation:
Let the length be l
Let the width be w
Since the length is 9 inches more than half the width.
Then;
L = 0.5w + 9
Perimeter of a rectangle is;
P = 2Lw
Thus;
P = 2w(0.5w + 9)
Since perimeter = 60
Then;
2w(0.5w + 9) = 60
w² + 18w = 60
w² + 18w - 60 = 0
From quadratic formula;
w ≈ 2.87 in
L = 0.5(2.87) + 9
L = 10.435 in
Answer:
t = 4
Step-by-step explanation:
Given
+ 3 = 5 ( subtract 3 from both sides )
= 2
Multiply both sides by 2 to clear the fraction
t = 2 × 2 = 4
