Mean = Sum of all the observations/ Number of observations = (87+46+90+78+89)/5 = 78
Variance = SD^2 ------ SD = Standard deviation
It means that with Variance, square root is never taken.
Therefore,
Variance = Summation of square of differences between observation and the mean divided by the number of observations.
That is,
Variance = {(87-78)^2 + (46-78)^2 + (90-78)^2 + (78-78)^2 + (89-78)^2}/5 = 274
Answer:26
Step-by-step explanation:
Y=1.25^x-2/5-10
Take log of both sides
So Y+10=1.25^x-2/5
So log to base 10 of the two sides of the equation is
Log(Y+10)=X-2/5log1.25.
To make X the subject, divide both sides by log1.25.
Log(Y+10)/log1.25=X-2/5.
Recall that Y was given to be 115
It becomes log(115 +10)/Log1.25=x-0.4
21.64=x-0.4
X=25.6
6hrs = school
9hrs = sleeps = 18hrs // 24hrs ----6hrs left
3hrs = plays
6hrs = other things
playing = 12.5% -- 3/24 3/24*100
other things = 25% -- 6/24 6/24*100
Answer:
C and E
Step-by-step explanation:
Have a great day! THanks!
