What is a factor of 21 but not a multiple of 7

A. 2 B. 3 C. 5 D. 4

Three minutes after a skydiver opens his parachute, he has descended 2,850 feet. After 5 minutes, he has descended 4,750 feet. If he descends at a constant rate throughout, how many feet did he descend in one minute?

It takes Evan 6 3/4 hours to mow 3 lawns. it takes him 2 1/3 hours to mow Mr. Smiths yard and 1 3/4 hours to mow Ms. Lee's yard. How many hours does it take to mow the third lawn?

4=6-2x? What is the value of x?

You discovered 1000 grams of an unknown element called Coolium 23 that has a half life 23 days. How long will it take for you to have 600 grams remaining.

An blank is a number sentence that uses the equal sign to show that two amounts are equal

A newspaper reporter wants to know how popular the hobby of bird watching is in the city. He asked people at the local bird refuge if they watched birds as a hobby. Which of the following best explains whether the reporters data is valid or not?

I am very confused on how to figure out if y = 3/4x is proportional?

Alison wants to buy a mountain bike for $339.12. If she saves $28.26 each month, in how many months will she be able to buy the bike?

At 12 o'clock the temperature was 7°C. The temperature decreased by - 20°C. What is the new temperature?

Ashleys rentals charges $27.50 per hour to rent a surfboard and a wetsuit. Darlas surf shop charges $23.25 per hour to rent a surfboard plus $17 extra for a wetsuit.