Answer:
a) 3/64 = 0.046 (4.6%)
b) 63/64 = 0.9843 (98.43%)
c) 1/64 = 0.015 (1.5%)
d) 1/4 = 0.25 (25%)
Step-by-step explanation:
in order to verify that the f(x) is a probability mass function , then it should comply the requirement that the sum of probabilities over the entire space of x is equal to 1. Then
∑f(x)*Δx = 1
if f(x)=(3/4)(1/4)^x , x = 0, 1, 2, ...
then Δx=1 and
∑f(x) = (3/4)∑(1/4)^x = (3/4)* [ 1/(1-1/4)] = (3/4)*(4/3) = 1
then f represents a probability mass function
a) P(X = 2)= f(x=2) = (3/4)(1/4)^2 = 3/64 = 0.046 (4.6%)
b) P(X ≤ 2) = ∑f(x) = f(x=0)+ f(x=1) + f(x=2) = (3/4) + (3/4)(1/4) + 3/64 = 63/64 = 0.9843 (98.43%)
c) P(X > 2)= 1- P(X ≤ 2) = 1 - 63/64 = 1/64 = 0.015 (1.5%)
d) P(X ≥ 1) = 1 - P(X < 1) = 1 - f(x=0) = 1- 3/4 = 1/4 = 0.25 (25%)
4x+4y..........................
The formula to find the perimeter of a rectangle is P= 2(l+w). By substituting what we now knowin to the equation:
•42=2(l+(2/5l)). We can have width represented at (2/5l) because it’s now 2/5 of the length. Now add them together to get a single coefficient for l.
•42= 2(7/5l). Multiplying 7/5 by 2.
42= (14/5l). Multiplying both sides by the reciprocal of 14/5, which is 5/14, to get l by itself.
•l= 15.
Now that we now know the value of l, we know that the length is 15m. To find the width of the answer, we then multiply 15 by 2/5, which equals 6. Therefore, the only third option is correct because the length is 15m and the width is 6m.
For 27) D
For 28) A
Hope that helps!
6 : 2/3.....multiply by 3
18 : 2...reduce
9:1 or 9/1