In a school, the ratio of the number of pupils to the number of teachers is 20:1. If the number of pupils is 840, how many teachers are there?

If there is 123 trees and 15% is you land how much is the rest

The period T (in seconds) of a pendulum is given by T=2/pi / sqrt ((L) / (32)), where L stands for the length (in feet) of the pendulum. If / pi = 3.14, and the period is 1.57 seconds, what is the length?

A ruler is 30 cm in length. A piece, x cm in length, breaks off. Write an expression for the length that is left.

What are the dangers of having overdraft protection?

What is the quotient of 396 divided by 12?

John had 84 dollars, and his brother Fred owed 12 dollars to his friend. John gave his brother some money. Fred paid his debt and now both of them has the same amount left. How much money did John give Fred?

True or false: dilations map angles of the same degrees

The rental fee for a bike is $4 plus $1.50 per hour. Write an equation in slope-intercept from that models this situation.

Share 200 in the ratio 3:1:4

Write the 5 digit number: a) number consists of 3 different digits b) all digits are even numbers greater than zero c) value of ones digit is 1/10 value of tens digit d) value of the tenths digit is 10 times as much as the value of the hundreds