Question

Tuan is playing a game, but the spinner is incomplete. If the numbers in the sections of the spinner represent the probabilities of spinning each section, help him figure out the fraction for the missing section of the spinner.

1/4,1/4,1/5

Answer 1

The sum of the numbers should total to 1. Let us say that x is the missing number, therefore:

x + ¼ + ¼ + 1/5 = 1

x = 1 – ¼ - ¼ - 1/5

The numbers should have similar denominator:

x = 20/20 – 5/20 – 5/20 – 4/20

x = 6/20

x = 3/10