A number is chosen at random between 1 and 25 what is the probability that they number chosen is a square number or a factor of 8?

Number of square numbers under 25 = 1, 4, 9, 16 and 25

= 5 numbers

number of factors of 8 under 25 = 8, 16 and 24

= 3 numbers

number of good outcomes = 5 + 3

= 8 good outcomes

total outcomes = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 and 25.

= 25 outcomes

probability = good outcomes : total outcomes

= 8/25

The probability that they number chosen is a square number or a factor of 8 is 8/25.