Answer:
Step-by-step explanation:
Let x be the random variable representing the times a fire department takes to arrive at the scene of an emergency. Since the population mean and population standard deviation are known, we would apply the formula,
z = (x - µ)/σ
Where
x = sample mean
µ = population mean
σ = standard deviation
From the information given,
µ = 6 minutes
σ = 1 minute
the probability that fire department arrives at the scene in case of an emergency between 4 minutes and 8 minutes is expressed as
P(4 ≤ x ≤ 8)
For x = 4,
z = (4 - 6)/1 = - 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.023
For x = 8
z = (8 - 6)/1 = 2
Looking at the normal distribution table, the probability corresponding to the z score is 0.98
Therefore,
P(4 ≤ x ≤ 8) = 0.98 - 0.23 = 0.75
The percent of emergencies that the fire department arrive at the scene in between 4 minutes and 8 minutes is
0.75 × 100 = 75%
From what I learnt so far, there are 3 possible ways of finding whether ratios form a proportion
Answer:
03%
Step-by-step explanation:
In this situation Mickey should have drew first 7 cards that are not diamond and then on the 8th attempt she should draw an ace.
Let A be the event of drawing 7 cards which are not diamond and B the event of drawing an ace card. therefore required probability is P(A∩B)=P(A)*P(B)
Now, there are 13 diamonds and 39 other cards. Hence,
P(A)=(
)⁷=0.1335
After drawing 7 non-diamond cards, the 8th card must be a diamond.Hence,
P(B)=
=0.25
Hence, P(A∩B)=P(A)*P(B)=0.1335*0.25=0.033(approximately 0.03,i.e. 3%)
Therefore probability that Mickey will draw her first diamond on the 8th
attempt is 3%
Answer:
x = 14 D
Step-by-step explanation:
(18x + 36) / 3 = 6x + 12
6x + 12 = -16 + 8x
-6x . -6x
12 = -16 + 2x
+16 . +16
28 = 2x
/2 . /2
14 = x
The area of a pyramid is the sum of area of the base and the area of slant triangles.
The area of the base is 1.5 × 1.5 = 2.25 cm²
The slant height of each triangle, s is 3 cm
The area of the triangles = 1/2 × 1.5 × 3 × 4
= 9 cm²
Therefore, the area of the pyramid
=9 +2.25
= 11.25 cm²