Which formula should you use for variance?

Which formula should you use for standard deviation?

There are already 1,400 gallons of water in a swimming pool. If water is filling the pool at a rate of 25 gallons per minute, which expression indicates the amount of water, in gallons, in the swimming pool after m minutes?

Suatu balok memiliki luas permukaan 188 cm. jika lebar dan tinggi balok masing masing 8 cm dan 6 cm, tentukan panjang balok tersebut?

1. The sum of Sam's and Tom's ages is 70. Tom is four times as old as Sam. If you let s = Sam's age and t = Tom's age then you can use a system of equations. What are Sam's and Tom's ages?

What is the area of a circle with a diameter of 6 in? (A) 12π in (B) 36π in2 (C) 9π in2 (D) 36 in2

What is the value of s? 3/8 (s+9) = - 19

The kindergarten teacher wants to divide 1/2 of her classroom into 5 equal sections for stations

A train traveling at 30 miles per hour reaches a tunnel which is 9 times as long as the train. If the train takes 2 minutes to completely clear the tunnel, how long is the train in miles? (1 mile = 5,280 feet)

The cost for 7 dance lessons is $82. the cost for 11 is $122. write a linear equations to find the total cost C for L dance lessons. How much for 4 lessons?

What is 9.09 repeating as a fraction?

The number of gallons of water in a tank that already has 300 gallons in it after being filled at 35 gallons per minute for m minutes