When your multiplying fractions like these you always switch the second fractions numerator and demonator, the little numbers (sorry if wrong i got it from a website) on the corners of the fractions get added to the numerator.
So, you would switch the 10 and 3 in 10\3 making: 3\10, there is a 0 so you don't add anything to the numerator. In 4\5 there is a 2 by it so you add the 2 to the 4 in 4\5 making 1 1\5 or 6\5.
Now you multiply!! 6\5(or 1 1\5) x 3\10= 18\50 ^w^ have a nice day! (i tried my best with math)
count all the dots that are greater than 10. you'll get 6 dots. the question is asking for the dots 10 and fewer there is 40 dots in total so you subtract