°° Let's see -
If you turn the two fractions into decimals (which is not that hard), you can see which one is bigger.
4 ÷ 5 = 0.8, or 80%
7 ÷ 10 = 0.7, or, 70%
Now compare the two.
70% < 80%
Therefore, 7/10 is smaller than 4/5.
↑ ↑ ↑ Hope this helps! :D