So the mean is 72.97
We need to subtract the mean from each value and square it.
(65-72.97)^2= 63.5209
(68-72.97)^2=24.7009
(69-72.97)^2=15.7609
(70-72.97)^2=8.8209
(71-72.97)^2= 3.8809
(72-72.97)^2=0.9409
(90-72.97)^2=290.0209
(95-72.97)^2=485.3209
Now we add up the new values ( also consider their frequency) and find their mean.
Add the values
63.5209+(2 •24.7009=49.4018)+(5•15.7609=78.8045)+(8•8.8209=70.5672)+(7•3.8809=27.1663)+(3•0.9409=2.8227)+(2•290.0209=580.0418)+(2•485.3209=970.6418)= 1,842.967
Divide by total numburs to find the mean
1,842.967/ 30=61.43223333
The standar deviation is the square root of the mean so is
Square root of 61.43223333=7.837871735
Round to the nearest tenth
Standard Deviation is 7.8
Answer:
4 t - 7 = 2 t+ 13 is the required equation.
The number of race medals Tara has is t = 20 medals.
Step-by-step explanation:
Let the number of medals Tara has = t medals
So, the number of medal Anita has = 4( Medals of Tara) - 7
= 4t - 7
And the number of medals Gary has = 2 times (Medals of Tara) + 13
= 2(t) + 13 = 2t + 13
Now, Annita and Gary has same number of medals.
⇒ 4t - 7 = 2t+ 13
or, 4t - 2t = 7 + 13
⇒ 2t = 20
⇒ t = 20/2 = 10
or t = 10
Hence, the number of race medals Tara has is t = 20 medals
Answer:
-3, 9
Step-by-step explanation:
The constant is 4.
Answer is A. first one...
P = -3
G = 3
P = -G = -(3) = -3