Question

1)У лотереї розігруєтся 500 білетів з номерами 001-500. Витягають один білет. Яка імовірність того, що номер білета закінчуєтся двома одиницями? 2) у коробці лежать 10 карток, занумерованих числами від 1 до 10. Знайдіть імовірність того, що навмання вибрана картка матиме номер, на якому буде: непарне число

Answer 1

Probability of a ticket ending with two ones in a lottery

To calculate the probability of a ticket ending with two ones in a lottery, we need to determine the total number of possible outcomes and the number of favorable outcomes.

1) Total number of possible outcomes: - In this case, there are 500 tickets with numbers ranging from 001 to 500.

2) Number of favorable outcomes: - To find the number of tickets that end with two ones, we need to count the tickets that have numbers ending with "11". - The possible numbers ending with "11" are 011, 111, 211, 311, ..., 491, and 491. - There are 10 numbers ending with "11".

Now, we can calculate the probability using the formula:

Probability = Number of favorable outcomes / Total number of possible outcomes

Substituting the values:

Probability = 10 / 500 = 0.02

Therefore, the probability of the ticket number ending with two ones is 0.02 or 2%.

Probability of selecting a card with an odd number from a box

To calculate the probability of selecting a card with an odd number from a box containing 10 cards numbered from 1 to 10, we need to determine the total number of possible outcomes and the number of favorable outcomes.

1) Total number of possible outcomes: - In this case, there are 10 cards in the box.

2) Number of favorable outcomes: - To find the number of cards with odd numbers, we need to count the cards numbered 1, 3, 5, 7, and 9. - There are 5 cards with odd numbers.

Now, we can calculate the probability using the formula:

Probability = Number of favorable outcomes / Total number of possible outcomes

Substituting the values:

Probability = 5 / 10 = 0.5

Therefore, the probability of selecting a card with an odd number is 0.5 or 50%.