According to the empirical rule, roughly 68% of the scores fall between z = -1 and z = 1
You can use a calculator to get a more approximate answer. If you have a TI calculator, you can use the "normalcdf" function to type in normalcdf(-1,1)
The equation of a circle is (x-h)^2+(y-k)^2=r^2, where (h,k) is the center and r is the radius.
To find the radius, we would find the square root of 144, which is 12.
r=12
:)
"twelve decreased by twice a number" ---> 12 - 2x
"8 times the sum of number and 4" ---> 8(x + 4)
12 - 2x = 8(x + 4)
12 - 2x = 8x + 32 (distributive property)
12 = 10x + 32 (add 2x to both sides)
-20 = 10x (subtract 32 from both sides)
x = -2 (divide both sides by 10)
That's answer.
Answer:
9
Step-by-step explanation:
you can always use guess-and-check:
124 seems rather high
(6)P(2) = 6!/4! = 6x5 ≠ 72
(9)P(2) = 9!/7! = 9x8 = 72
