21A
The equation for buying 3 apples at x dollars each.
What is 3x?
An equation for finding a number when doubled is equal to 20.
What is 2x = 20?
An equation for the perimeter, P, of a square with side length s.
What is P = 4s?
An equation for a school having s students each needing n notebooks, resulting in a total of T notebooks.
What is T = sn?
An equation for a car travels at a constant speed, s, for t hours, write the equation for the distance, d, it covers.
What is d = st?
An equation for the number of slices, s, one can get from p pizzas if each pizza is cut into 8 slices.
What is s = 8p?
A number is tripled and then increased by 7 to get y. Write this as an equation.
What is y = 3x + 7?
A farmer who has h hens that each lay e eggs, write an equation for the total number of eggs, E.
What is E = he?
An equation for a movie theater has r rows with s seats in each row. Write the equation for the total number of seats, T.
What is T = rs?
An equation where you have b books to distribute evenly among f friends. Write the equation for the number of books each friend gets, B.
What is B = b/f?
An equation for the volume, V, of water in a tank that holds g gallons per inch of height, h.
What is V = gh?
If the difference between five times a number, x, and 6 is 44, write an equation to represent this.
What is 5x - 6 = 44?
The equation for a circle's circumference, C, is four times its radius, r.
What is C = 4πr?
An equation for the future value, F, of an investment, P, compounded annually at a rate r for t years.
What is F = P(1 + r)t?
An equation for the total number of pages, P, you will read if you read b books, each with n pages.
What is P = bn?
Write an equation if a car's value, V, decreases at a rate of d percent per year, from its original value, O, after t years.
What is V = O(1 - d/100)t?
If the square of a number, x, decreased by the product of the number and 9 is equal to 20, write this as an equation.
What is x2 - 9x = 20?
Write an equation if the interest, I, earned on a principal, P, after n years at a simple interest rate r per annum is to be tripled.
What is I = 3Pnr?
Given an isosceles triangle with base b and equal sides e, write an equation for its perimeter, P.
What is P = 2e + b?
Write an equation for the total surface area, A, of a cube with edge length s.
What is A = 6s2?
If the sum of the squares of two consecutive integers, n and n+1, equals 61, write an equation to represent this relationship.
What is n2 + (n+1)2 = 61?
Write an equation if the product of two numbers is 24, and their sum is S.
What are xy = 24 and x + y = S?
The sum of the squares of two consecutive positive integers is 365. Write an equation to represent this situation.
x2 + (x + 1)2 = 365.
A boat is traveling upstream in a river with a current of 5 miles per hour. The boat can travel at a speed of 15 miles per hour in still water. If it takes the boat 4 hours to travel a certain distance upstream, write an equation and solve for the distance.
d = (15 - 5) * 4
The sum of the ages of three siblings is 70. The oldest sibling is 3 years older than twice the age of the youngest sibling. The middle sibling is 2 years older than the youngest sibling. Write an equation for the age of the youngest sibling (y).
y + (y+2) + (2y+3) = 70.