Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at r...
Problem Analysis:
We have 20 tickets numbered from 1 to 20. We need to find the probability that the ticket drawn has a number which is a multiple of 3 or 5. To solve this problem, we need to determine the total number of favorable outcomes (tickets with numbers that are multiples of 3 or 5) and the total number of possible outcomes (all the tickets).
Solution:
1. Total Number of Possible Outcomes:
There are 20 tickets in total, so the total number of possible outcomes is 20.
2. Total Number of Favorable Outcomes:
We need to find the total number of tickets that have numbers which are multiples of 3 or 5. To do this, we can determine the number of tickets that are multiples of 3, the number of tickets that are multiples of 5, and subtract the number of tickets that are multiples of both 3 and 5 (multiples of 15) to avoid double counting.
- Number of tickets that are multiples of 3:
To find the number of tickets that are multiples of 3, we can divide 20 by 3 and take the integer part of the quotient. This gives us 6. So, there are 6 tickets that are multiples of 3.
- Number of tickets that are multiples of 5:
To find the number of tickets that are multiples of 5, we can divide 20 by 5 and take the integer part of the quotient. This gives us 4. So, there are 4 tickets that are multiples of 5.
- Number of tickets that are multiples of both 3 and 5 (multiples of 15):
To find the number of tickets that are multiples of both 3 and 5, we can divide 20 by 15 and take the integer part of the quotient. This gives us 1. So, there is 1 ticket that is a multiple of both 3 and 5.
Therefore, the total number of favorable outcomes is 6 + 4 - 1 = 9.
3. Probability Calculation:
The probability is calculated by dividing the total number of favorable outcomes by the total number of possible outcomes.
Probability = Number of Favorable Outcomes / Number of Possible Outcomes
Probability = 9 / 20
Therefore, the probability that the ticket drawn has a number which is a multiple of 3 or 5 is 9/20.
Answer:
The correct answer is option D) 9/20.
Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at r...
D)3*3= 9
3*4=20
9/20
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