Answer:
a) 0.1108
(b) 0.0173
Step-by-step explanation:
We are given that 20% of all stock investors are retired people. A random sample of 25 stock investors is taken.
Firstly, the binomial probability is given by;
where, n = number of trails(samples) taken = 25
r = number of successes
p = probability of success and success in our question is % of
retired people i.e. 20%.
Let X = Number of people retired
(a) Probability that exactly seven are retired people = P(X = 7)
P(X = 7) =
= = 0.1108
(b) Probability that 10 or more are retired people = P(X >= 10)
P(X >= 10) = 1 - P(X <= 9)
Now, using binomial probability table, we find that P(X <= 9) is 0.98266 at n = 25, p = 0.2 and x= 9
So, P(X >= 10) = 1 - 0.98266 = 0.0173.
Answer:
99
Step-by-step explanation:
Surface area of cylinder is 2 (pi)rh+2(pi)r^2
this is the area of the side [(2 (pi)rh] and the two circles together [2 (pi)r^2]
122. r=24
h=15
2 (3.14)24×15+2 (3.14)24^2
6.28×24×15+6.28×24^2
2260.8+3617.28
5878.08mm
123. r=5
h=8
2 (3.14)5×8+2 (3.14)5^2
6.28×5×8+6.28×5^2
251.2+157
408.2cm
124. the surface area of a cylinder that has a hole is going to be
surface area of big cylinder-2small area circles (the holes) + the area of the holes sides
hopefully that isn't too confusing
big radius: 8
height: 14
little radius: 2.5
height: 14
2 (3.14)8×14+2 (3.14)8^2
6.28×8×14+6.28×8^2
703.36+401.92
1105.28in (area of big cylinder)
2 (3.14)2.5^2 (two small holes)
6.28×2.5^2
39.25in (area of holes)
2 (3.14)×2.5×14 (area of side)
6.28×2.5×14
219.8in
1105.28-39.25+219.8
1066.03+219.8
1285.83in total surface area
125. h=20
r=6 since diameter is a foot or 12 in, half of that is 6
2 (3.14)6×20+2 (3.14)6^2
6.28×6×20+6.28×6^2
753.6+226.08
979.68in
126. first radius= 10
first height = 6
second radius= 6
second height= 10
2 (3.14)10×6+2 (3.14)10^2
6.28×10×6+6.28×10^2
376.8+628
1004.8in (surface area of first cylinder)
2 (3.14)6×10+2 (3.14)6^2
6.28×6×10+6.28×6^2
376.8+226.08
602.88in (surface area of second cylinder)
1004.8-602.88= 401.92
the surface area of the cylinder with radius 10 and height 6 is GREATER that the surface area of the cylinder with radius 6 and height 10..
by 401.92in
Answer:
d
Step-by-step explanation:
Answer:
x = 27
Step-by-step explanation:
4(x−9)=4(9+1/3x).
Divide each side by 4
(x−9)=(9+1/3x)
Subtract 1/3 x from each side
x - 1/3x -9 = 9+1/3x -1/3x
2/3x -9 = 9
Add 9 to each side
2/3x -9+9 = 9+9
2/3x = 18
Multiply each side by 3/2
3/2 * 2/3x = 18*3/2
x = 27
