0000:00:00:00:00Start9Number 9ExplanationIn a housing cluster, every house has a number consisting of two digits. The digits used are whole numbers less than 101010. Then the number of possible house numbers where all digits are odd is ....101010252525303030353535505050ExplanationWe will use the multiplication rule (filling slots) to form the two-digit house numbers. Identifying Available Digits Whole numbers less than 101010 are {0,1,2,3,4,5,6,7,8,9}\{0, 1, 2, 3, 4, 5, 6, 7, 8, 9\}{0,1,2,3,4,5,6,7,8,9}. The condition is that all digits must be odd. Therefore, the allowed digits are: {1,3,5,7,9}\{1, 3, 5, 7, 9\}{1,3,5,7,9} There are 555 odd digits available. Since the house number consists of two digits, we have two positions to fill: First Digit: Can be chosen from the 555 odd digits. Second Digit: Can also be chosen from the 555 odd digits (repetition is allowed). Calculating Total Possibilities The total number of possibilities is the product of the choices for each position: Total=5×5=25\text{Total} = 5 \times 5 = 25Total=5×5=25 So, there are 252525 possible house numbers.
9Number 9ExplanationIn a housing cluster, every house has a number consisting of two digits. The digits used are whole numbers less than 101010. Then the number of possible house numbers where all digits are odd is ....101010252525303030353535505050ExplanationWe will use the multiplication rule (filling slots) to form the two-digit house numbers. Identifying Available Digits Whole numbers less than 101010 are {0,1,2,3,4,5,6,7,8,9}\{0, 1, 2, 3, 4, 5, 6, 7, 8, 9\}{0,1,2,3,4,5,6,7,8,9}. The condition is that all digits must be odd. Therefore, the allowed digits are: {1,3,5,7,9}\{1, 3, 5, 7, 9\}{1,3,5,7,9} There are 555 odd digits available. Since the house number consists of two digits, we have two positions to fill: First Digit: Can be chosen from the 555 odd digits. Second Digit: Can also be chosen from the 555 odd digits (repetition is allowed). Calculating Total Possibilities The total number of possibilities is the product of the choices for each position: Total=5×5=25\text{Total} = 5 \times 5 = 25Total=5×5=25 So, there are 252525 possible house numbers.
