a) 2 (5x-3) = 24
= 10x -6 = 24
= 10x = 24+6
= 10x = 30
= x= 30/10
b) 5 (2x+1) = 50
= 10x+5=50
= 10x = 50-5
= 10x = 45
= x = 45/10
c) (3x+4)/2=9.5
= (3x+4)/2=95/10
( On cross multiplication )
= 10(3x+4) = 2×95
= 30x+40=190
= 30x=190-40
= 30x=150
= x=150/30
(on simplification)
d) (7+2x)/3=5
(On cross multiplication)
= 1(7+2x)=5(3)
= 7+2x=15
= 2x=15-7
= 2x=8
= x=8/2
(on dividing)
Answer:
0.7486 = 74.86% observations would be less than 5.79
Step-by-step explanation:
I suppose there was a small typing mistake, so i am going to use the distribution as N (5.43,0.54)
Problems of normally distributed samples can be solved using the z-score formula.
In a set with mean and standard deviation
, the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.
The general format of the normal distribution is:
N(mean, standard deviation)
Which means that:
What proportion of observations would be less than 5.79?
This is the pvalue of Z when X = 5.79. So
has a pvalue of 0.7486
0.7486 = 74.86% observations would be less than 5.79
