There are only blue cubes, red cubes and yellow cubes in a box. The number of red cubes in the box is the same as the number of yellow cubes in the box.
a) Complete the table

There are 30 blue cubes in the box.
b) What is the total number of cubes in the box?

Total probability equals 1.

Subtract the probability of blue from 1:

1-0.4 = 0.6

Red and yellow total is 0.6

Since they have the same number of cubes, the probability of both would be the same so divide the remainder by 2:

0.6 /2 = 0.3

The probability of red is 0.3

The probability of yellow is 0.3

30 blue cubes with a probability of 0.4.

Let total cubes = x

30 blue/ x = 0.4

Multiply both sides by x:

30 = 0.4x

Divide both sides by 0.4

X = 30/0.4

X = 75

Total cubes is 75

This doesn’t make sense though because red and yellow are supposed to be the same and if you subtract blue from total it’s an odd number so red and yellow aren’t the same:

75-30 = 45

45/2 = 22.5