Question

Least to greatest. 13.01, 13.1, 13.001

Answer 1

13.001
13.01
13.1

$13.001=13\dfrac{1}{1000} < 13.01=13\dfrac{1}{100} < 13.1=13\dfrac{1}{10}$

Answer 2

13.001, 13.01, 13.1

to put it more visually, i'll show in fractions.

13.001 = 13 1/1000
13.01= 13 1/100
13.1 = 13 1/10

a piece out of 10 would be bigger than a piece out of 1000 because in that case there are many more pieces and they'll have to be smaller to make up the whole.

hope this helps.