Answer:
Q6. D
Q8. A
Step-by-step explanation:
Q6. In 40 trials, he flipped '2 heads and 1 tail' 16 times.
For 2 heads, probability= 16/40= 4/10
For 120 trials, number of times= 4/10 × 120= 48
Q8.
Answer is A because the inequality shows that x is equal or greater than 8 so the dot at 8 has to be coloured.
Note that we do not change the inequality sign unless we are dividing the whole thing by -1.
Answer:
Approximately 16% of adult women have feet longer than 27.2 cm.
Step-by-step explanation:
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean and standard deviation
, the z-score of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.
The feet of the average adult woman are 24.6 cm long
This means that
16% of adult women have feet that are shorter than 22 cm
This means that when , Z has a p-value of 0.16, so when
. We use this to find
Approximately what percent of adult women have feet longer than 27.2 cm?
The proportion is 1 subtracted by the p-value of Z when X = 27.2. So
has a p-value of 0.84.
1 - 0.84 = 0.16
0.16*100% = 16%.
Approximately 16% of adult women have feet longer than 27.2 cm.