Convert 30/7 into a mixed number

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a. m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?

Equation for the calculation double 2 and then add 5

Which of these tools or constructions is used to inscribe a hexagon inside a circle?