There are 20 numbers in total from 1 to 20. The even numbers in this range are 2, 4, 6, 8, 10, 12, 14, 16, 18, and 20, totaling 10 even numbers. Therefore, the probability of picking an even number is the number of even numbers divided by the total numbers, which is ( \frac{10}{20} = \frac{1}{2} ). Thus, the probability of selecting an even number is 0.5 or 50%.
From 75 to 100 (inclusive), there are 26 numbers, and 13 of them are odd.The probability of picking an odd number is 13/26 = 50%.
3 out of 4
50 50 odd or even same probability
Using the formula n!/r!(n-r)! where n is the number of possible numbers and r is the number of numbers chosen, there are 13983816 combinations of six numbers between 1 and 49 inclusive.
The probability is(the total number of numbers on the spinner minus 5)/(the total number of numbers on the spinner)Another way to express the same probability is1 - 5/(the total number of numbers on the spinner)
There are 8 out of 20 numbers that are prime, so 8/20, or 2/5.
From 75 to 100 (inclusive), there are 26 numbers, and 13 of them are odd.The probability of picking an odd number is 13/26 = 50%.
3 out of 4
15/49ExplanationThere are 15 prime numbers between 1 and 49 (2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47). If you randomly choose one natural number from the 49 numbers between 1 and 49 inclusive, there is a 15/49 probability that it will be prime.
1 out of 20 this is because there are 20 numbers in total, and there is only one 7 in there. (Assuming that there is the same probability for each number to be chosen, and that 17 is excluded as an affirmative outcome)
50%
1/3
There are 12 composite (and 8 primes) in the first twenty whole numbers. So the probability of randomly choosing a non-prime is 12/20 or 60%.
the first 10 whole numbers are numbers 1 to 10 and in those numbers only 3 numbers are divisible by 3 in which 3, 6 and 9 therefore the probability of from those figures that the numbers won't be divisible by 3 is 7/10 or 70%.
Assuming no repetition is allowed, there are 8582777280 ways in which you can pick any of the numbers from 1 to 99 inclusive with 5 numbers. This is given by the formula n! / (n - r)! where n is the number of numbers you have to choose from, and r is the number of numbers chosen.
50 50 odd or even same probability
A probability must needs be a number between 0 and 1 (often expressed as 0% and 100%), inclusive.