How can i use compatible numbers to find estimates for 478 divided by 12

Which formula finds the probability that a point on the grid below will be in the blue area? p(blue) = total number of squares number of blue squares number of blue squares p(blue) = total number of squares number of blue squares p(blue) = number of white squares

How do i make someone brainliest? (if you answer me, i might be able to make you brainliest! )

Ametal rod is 2/5 meters long. it will be cut into pieces that are each 1/30 meters long. how many pieces will be made from the rod?