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:
Infinitely many solutions
Step-by-step explanation:
2y=14-2x
y=-x+7
------------
2(-x+7)=14-2x
-2x+14=14-2x
-2x-(-2x)=14-14
-2x+2x=0
0=0
infinitely many solutions
This makes a right triangle with hypotenuse x+2 and legs 10 and x
10²+x²=(x+2)²
100 + x² = x²+4x+4
100=4x+4
4x=96
x=24, the height we are looking for
To answer this we will add, but before we add we will change 4/5 in to a decimal. to change ANY fraction into a decimal we have to divide the numerator by the denominator. lets do it:-
4/5
4 ÷ 5 = 0.8
Now lets substitute 0.8 for 4/5 and then add.
4/5 + 0.05
0.8 + 0.05 = 0.85
CHECK OUR WORK:-
0.85 - 0.8 = 0.05
We were RIGHT!!
So, the decimal 0.85 is equivalent to 4/5 + 0.05.
Hope I helped ya!! xD
