1. BuzzFeed / Flickr: franklinheijnen
Correct!
Wrong!

Mode is the value that appears most often in a set of data, so you can have more than one mode. For example in the set of numbers 1, 1, 2, 2, 3, 4, 5 both 1 and 2 would be the mode.

2. Correct!
Wrong!

5 multiplied by 3 is 15.

3. BuzzFeed / Flickr: calsidyrose / Creative Commons
Correct!
Wrong!

Add c to both sides, then subtract a to get c = b - a.

4. Correct!
Wrong!

The median is the one in the middle when you arrange a set of numbers in order. In this case there are eight in total, so the median is half way between the 4th and 5th numbers in the set.

5. Correct!
Wrong!

≥ means greater than or equal to, so the sequence starts at 2 and goes up.

6. Correct!
Wrong!

Add the indices: 2 + 3 = 5.

7. Correct!
Wrong!

I mean it's basically a straight line.

8. Correct!
Wrong!

You couldn't draw a line to fit these points, so no correlation.

9. BuzzFeed / Flickr: 54943750@N00 / Creative Commons
Correct!
Wrong!

Multiplying two negative numbers makes a positive one.

10. Correct!
Wrong!

If the next digit down is 5 or greater, you round up. We only want one significant figure, so that gives us 5000.

11. Correct!
Wrong!

3 goes into 9 three times, so you have to multiply the 4 by three to get 12.

12. BuzzFeed / Flickr: chadskeers / Creative Commons
Correct!
Wrong!

2% is equal to 2 divided by 100, which gives you 0.02.

13. Correct!
Wrong!

8 goes into 40 five times and into 24 three times. There's no larger number that goes into them both.

14. Correct!
Wrong!

You add the indices. The trick is to remember that "b" is actually "b~1~", you just don't have to write the 1 out.

15. Correct!
Wrong!

There are 8 green counters out of a total of 20. 8/20 simplifies to 2/5. Ta da!