The mean of 2 numbers is 8. One of the numbers is 2. What is the other number

1) The mean of 2 numbers is 8. One of the numbers is 2. What is the other number?

2) A fair spinner has 8 equal sections with a number on each section. Five of them are even numbers. Three are odd numbers. What is the probability that I spin an even number?

3) Using 3 as an approximation for pi, what is the area of a circle with radius 5cm?

1) The mean of two numbers (let's say x and y) is 8 means that (x + y) / 2 = 8. If one of the two is 2, let's say x, then (2+y) / 2 = 8, so 2 + y = 16, so y = 14.

2) Spinning the spinner you have 8 possible outcomes; three of them will give you and odd number, and five an even number, so you have a 5/8 probability of getting an even number.

3) The area of a circle of radius x is pi*r^2, so, if the radius is 5cm and pi is 3, the area is 3*(5cm)^2, which is 75.

1) Total = 2*8 =16. Therefore, missing number is 16 - 2 = 14.
2) 5/8
3) Pi*r^2 = 3*5^2 = 75

1) The other number is 14 because (2+x)/2 = 8 --> x = 16-2 = 14

2) 5/8 = 0.625

3) Area of circle = pi * r^2 = 3 * 5^2 = 75 cm^2

let x be other number, then
(2+x)/2=8, then solve.
x=14.

) The mean of 2 numbers is 8. One of the numbers is 2. What is the other number?

Other number =14

mean = (2+x)/2 = 8
=> 2 + x = 16
=> x = 16 -2 = 14
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2) P = 5/8
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3) Pi*r^² = 3*5² = 75
Answer