1. 
Olivia is grinding a part for a spacecraft to be sent on a mission to mars. The part must be very precise. Right now it is oversized by 2.5 x 10^{4} inches. If she makes two passes with the grinding machine and takes off half the required amount each time, how much will be ground off on each pass?


2. 
If there are five million yeast cells per milliliter of growth medium in an experiment, how many will there be in two days when the cell population has quadrupled and then quadrupled again? Express your answer using scientific notation.


3. 
If 7.3 x 10^{9} pieces of sand are combined with 3.6 x 10^{9} pieces of sand, how many pieces of sand are there all together?


4. 
William gave Jonathan a challenge. "I think I can write the number one hundred sixty million using fewer zeros than you," said William. "I don't think so," replied Jonathan. In the end it was a draw (William was wrong). How did they do it using only one zero?


5. 
* This is a premade sheet. Use the link at the top of the page for a printable page. 

6. 
With the help of Mr. Bloop, some middle school students measured the growth rate of a fungus. An old fashioned (but still useful) apparatus called a race tube was used. A small piece of the fungus was placed at one end of a long tube that had a layer of growth medium filling it about half way. Then the distance the fungus grew down the tube was measured each day. At the end of two weeks the fungus had advanced 38 cm along the tube. What was the average speed of advance of the fungus in m/s? Express your answer using scientific notation.

