Question

Bingo uses the numbers 1 to 75. If you randomly select a number, What is the probability it will not be a multiple of 7? Express your answer as a fraction.

Answer 1

There are 7 multiples of 10 from 1-75.
There are 75 integers from 1-75.
75 total integers - 7 multiples of 10 = 68 other multiples.
68 others/75 total 

=68/75

Answer 2

Answer:

$\text{The probability that the selected no. is not a multiple of 7 = }\frac{13}{15}$

Step-by-step explanation:

Numbers used by Bingo for selection = 1 to 75

Multiples of 7 from 1 to 75 : 7, 14, 21, 28, 35, 42, 49, 56, 63, 70

No. of multiples from 1 to 75 = 10

Total numbers from 1 to 75 = 75

$\text{Probability that the selected no. is multiple of 7 = }\frac{10}{75}\\\\\text{Probability that the selected no. is not a multiple of 7 = }1-\frac{10}{75}\\\\=\frac{75-10}{75}\\\\=\frac{65}{75}\\\\=\frac{13}{15}$

$\text{Hence, The probability that the selected no. is not a multiple of 7 = }\frac{13}{15}$