How many whole numbers less than 500 can be formed using the digits 1, 2, 4, and 5
Let S = {2, 3, 4, 5, 6, 7, 9}. How many different 3-digit numbers (with all digits different) from S can be made which are less than 500?This question was previously asked in Show
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Answer (Detailed Solution Below)Option 3 : 90 Free Electric charges and coulomb's law (Basic) 10 Questions 10 Marks 10 Mins Explanation:  We can solve this by filling the places according to the question Step 1: Since the Number should be less than 500 So, there are only 3 possibilities at 1 st place i.e. (2, 3, 4) Step 2: According to the question Repetition is not allowed we have to fix one number (let 2) in the 1st place Now, At 2nd place, there are a total of 6 ways (3, 4, 5, 6, 7, 9) Step 3: According to the question Repetition is not allowed we have to fix one number (let 3) in the 2nd place Now, At 3rd place, there are a total of 5 ways (4, 5, 6, 7, 9) ∴ The total number of different 3-digit numbers less than 500 = 3 × 6 × 5 = 90. Last updated on Nov 17, 2022 Union Public Service Commission (UPSC) has released the NDA Result I 2022 (Name Wise List) for the exam that was held on 10th April 2022. 519 candidates have been selected provisionally as per the results. The selection process for the exam includes a Written Exam and SSB Interview. Candidates who get successful selection under UPSC NDA will get a salary range between Rs. 15,600 to Rs. 39,100.
How many even numbers less than 500 can be formed using the digits 1,2,3,4,5? Each digits may be used only once in any number. #1 (2, 4, 12, 14, 24, 32, 34, 42, 52, 54, 124, 132, 134, 142, 152, 154, 214, 234, 254, 312, 314, 324, 342, 352, 354, 412, 432, 452) = 28 such numbers #2 Well we know the digit must end in 2 or 4, because it has to be even. So 1, 3, 5, can't be the ending digit. We've chosen 2 digits already (2 and 4), so there are 3 possibilities for the first digit. It can't be 5, because then it would exceed the count of 500, so 1, 3, or whatever's left of 2 and 4. And only 3 digits left for the middle digit. So that means 2 * 3 * 3 = 18 cases for 3 digit numbers.. Now what about 2 digit numbers? Having chosen 2 or 4, we have 4 other possibilities left. So 2 * 4 = 8 cases for 2-digit numbers. We have to remember 1 digit numbers, 2 or 4, so 2 cases. In the end: 18 + 8 + 2 = 28 numbers. 13 Online UsersCase $1$: The number is a single digit. In this case, the only even numbers are $2$ and $4$, giving a total of $2$. Case $2$: The number has exactly two digits. In this case, the last digit must be either $2$ or $4$, and the first digit must be one of the other four digits allowed, giving a total of $2 \cdot 4=8$. Case $3$: The number has exactly three digits. In this case, the last digit must be either $2$ or $4$ and the middle digit must be one of the other four digits allowed. If the middle digit is $5$, then the first digit must be one of the other three digits allowed, giving a total of $2 \cdot 3=6$. If the middle digit is not $5$, then the first digit must be one of two digits other than the last two digits and $5$, giving a total of $2 \cdot 3 \cdot 2=12$. So, there are $2+8+6+12=28$ even numbers less than $500$ with distinct digits $\in \{1,2,3,4,5\}$. How many even numbers less than 500 can be formed using the digits?Each digit may be used only once in any number. But the answer is 28.
How many 3By the product rule, there are 2⋅6=12 2 ⋅ 6 = 12 ways to choose the three-digit number. There are 12 different three-digit numbers less than 500 made using the digits 3,4,5,6 if the digits can be used only once.
How many even numbers formed by using all the figures 1 2 3 4 and 5 only once?Therefore, there are 48 even numbers that can be formed using 1,2,3,4 and 5 only once.
How many whole numbers less than 100 Cannot be divided exactly by 4 or 5?So, for example, pro-add(8) = 8 x8 +8 = 72. 19. How many whole numbers less than 100 cannot be divided exactly by 4 or by 5? 20.
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