Answer:
<u>P(three tails) = 27/125 or 21.6%</u>
<u>P(two tails followed by one head) = 18/125 or 14.4%.</u>
Step-by-step explanation:
1. Let's review the information provided to us to answer the questions correctly:
Probability of getting a head when a biased coin is tossed = 2/5
therefore,
Probability of getting a tails when a biased coin is tossed = 3/5
2. Find the following probabilities and select the correct solution.
P(three tails) =
3/5 * 3/5 * 3/5 = 27/125 or 21.6%
P(two tails followed by one head) =
3/5 * 3/5 * 2/5 = 18/125 or 14.4%.
675 people will have score between 85 and 120
Step-by-step explanation:
Given
Mean = 100
SD = 15
If we have to find percentage of score between two values we have to find the z-score for both values and then area under the curve for both values
z-score is given by:
for a value x:

So,
For 85:


Now we have to find the area under the curve for both values of z-score. z-score tables are used for this purpose.
So,
For z1 : 0.1587
For z2: 0.9082
The area between z11 and z2:

So the probability of score between 85 and 120 is 0.7495
As the sample is of 900 people, the people with scores between 85 and 120 will be:
900*0.7495 = 674.55 people
Rounding off to nearest whole number
675 people will have score between 85 and 120
Keywords: Probability, SD
Learn more about probability at:
#LearnwithBrainly
36.54
45% of 81.2 is 36.54.
U use sin
sin50 = b/10
b=10(0.76)
b=7.6