3 times the product of 5 and b is reduced by 2
3*(5*b)-2
15b-2
Answer:
6f = 24
f = 4
Step-by-step explanation:
Answer:
25
Step-by-step explanation:
The Empirical Rule states that, for a normally distributed random variable:
68% of the measures are within 1 standard deviation of the mean.
95% of the measures are within 2 standard deviation of the mean.
99.7% of the measures are within 3 standard deviations of the mean.
In this problem, we have that:
Mean = 175cm
Standard deviation = 6 cm
Percentage of students below 163 cm
163 = 175 - 2*6
So 163 is two standard deviations below the mean.
By the Empirical rule, 95% of the heights are within 2 standard deviations of the mean. The other 100-95 = 5% are more than 2 standard deviations of the mean. Since the normal distribution is symmetric, 2.5% of them are more than 2 standard deviations below the mean(so below 163cm) and 2.5% are more than two standard deviations above the mean.
2.5% of the students have heights less than 163cm.
Out of 1000
0.025*1000 = 25
25 is the answer
Answer:
Step-by-step explanation:
Given is the probability distribution of a random variable X
X 4 5 6 7 Total
P 0.2 0.4 0.3 0.1 1
x*p 0.8 2 1.8 0.7 5.3
x^2*p 3.2 10 10.8 4.9 28.9
a) E(X) = Mean of X = sum of xp = 5.3
Std dev = square root of variance = 0.9
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b) For sample mean we have
Mean = 5.3
Variance = var(x)/n = 
c) 
Option B is the correct answer
Step-by-step explanation:
Step 1 :
Given,
Maximum budget Sandra has for the trip is $90
Fixed rental fee = $30
Daily fee = $10
Step 2 :
Let x be the number of the days for which Sandra can go for the trip
If the daily fee is $10, the cost for x number of days would be 10*x
the fixed fee is $30
So the equation is represent the cost of the trip is 30 + 10 x
given that the maximum budget is $90, the above cost should always be less $90
So the required inequality is 30 + 10x ≤ 90
Option B is the correct answer
