if the fractions do not have the same denominator, or bottom number, you have to convert them . Both 10 and 8 go into 40, so converted 4/10 is equal to 16/40 ( 10X4) (4X4) 3/8 is 15/40 (8X5) (5X) so since 16 is greater than 15, 4/10 is greater than 3/8.