Question

I need help on knowing which number is greater and what sign to use between 5.91 and 5.1

Answer 1

To solve this we have to look at the number line:

We can see that if we move from left to right, 5.91 is greater than 5.1.

The sign used to represent this is:

5.1 < 5.91

Always the little part points to the smaller number.