The probability of picking a blue envelope is 2/8 = 1/4. You want to select a blue envelope twice with replacement so we multiply 1/4*1/4 which is 1/16.
You can start by drawing a number line and labeling it with eighths. ( 1/8, 2/8, etc.) Then you can place a dot on 3/8 and 5/8. From there, it's clear to see that 5/8 is greater than 3/8.
