Answer:
75
Step-by-step explanation:
The computation of the total number of cubes in box is shown below:
Given that
The probability of blue = 0.4
For red it is 0.3
And, for yellow it is 0.3
As if there is 30 blue cubes in a box
So for red it is = 30 × 0.3 ÷ 0.4 = 22.5
And, for yellow = 30 × 0.3 ÷ 0.4 = 22.5
Now the total number of cubes in a box is
= 30 + 22.5 + 22.5
= 75
