how many of the first 80 positive integers can he written as the sum of two distinct powers of 3? for example, 28=27+1=3^3+3^0 can be expressed, but 29 cannot be.

1/2b+9/4=7/4 solve the equation

Explain what the mean absolute deviation is in general. Explain what the MAD means in the context of Robin and Evelyn's data.

You have 24 seashells and give 8 seashells to your sister. You arrange the rest of the seashells into 4 equal rows. Which steps can you use to find the number of seashells in each row?

Seven less than four times a number equals 13

How to find the area of an octagon. Just the formula.

A sandwich shop has three types of sandwiches: ham, turkey, and chicken. Each sandwich can be ordered with white bread or wheat. Customers can add any combination of the four available toppings.

When my teacher says find (a) but i found it, what does she mean?

You order 4 fish sandwiches and a hamburger. The cost of the hamburger is $2.50 your total bill before taxes $14.30. Write and solve an equation to find the cost of a fish sandwich.

Elliot is standing at the top of a store escalator that leads to the ground floor below. The angle of depression from the top of the escalator to the floor is 42.51 degree, and the escalator is 16 feet long.

A cube has a lateral area of 9 square centimeters. What is the length of each edge of the cube?