How can tou determine whether or not a number is rational?

Mrs. Johnson spent $611 buying lunch for 78 students. If all the lunches cost the same, about how much did she spend on each lunch?

What is the simplified form of 3a^4b^-2c^3

D=6, Dx=-6, Dy=-24, Dz=-30 what is the solution set

2/5+4/7 estimate: decide if each addend is closer to 0 or closer to 1. then estimate the sum or difference. this is a fraction question.

The simple interest on $600.00 at 5% per year for two years is?

A helicopter leaves central airport and flies north at 180 mi/hr. Twenty minutes later a plane leaves the airport and follows the helicopter at 330mi/hr. How long does it take the plane to overtake the helicopter

A rectangular piece of paper with length 29 cm and width 12cm has two semicircles cut out of it. Find the area of the paper that remains.

Kent earns $49,000 a year and has to pay $45 in taxes for every $1,000. How much taxes does he pay in one year? A. $2,049 B. $2,000 C. $2 205 D. $1,000

What is the surface area of a right rectangular prism whose dimensions are 3 by 6 by 8?

I am a two-digit number Both of my digits are even I am the product of two consecutive whole numbers The sum of my digits is greater than the product of my digits