Table of Contents
- 1 How many three digit number ABC are formed by at least two of the three digits are same?
- 2 How many three-digit numbers are there such that the sum of the digits in each number is 10?
- 3 How many three digit positive integers have exactly two digits that are the same?
- 4 How many 3 digit numbers are there such that the difference between consecutive digits must be 3?
- 5 How many digits are left for tens place in the GRE?
How many three digit number ABC are formed by at least two of the three digits are same?
Third digit can be filled with remaining 8 digits. Hence the number of three digit numbers formed such that at least 2 of its digits are same are 252.
How many three-digit numbers are there such that the sum of the digits in each number is 10?
Originally Answered: How many 3-digit numbers are there such that the sum of their digits is equal to 10? There are 54 numbers.
How many numbers satisfy the condition a 3 B 3 C 3 ABC where ABC is three digit number choices?
= 5040, which is a four-digit number. But abc is a three-digit number. If any of the digits in abc is 7, 8, or 9, we will get a four-digit number.
How many three digit positive integers are there such that at least two of its digits are the same?
. Thus, there are 252 numbers that are 3-digit numbers that have at least 2 digits that have the same value.
How many three digit positive integers have exactly two digits that are the same?
there are 9∗9∗8 three digit numbers where all digits are different so 1000−9∗9∗8 which have at least two digits that are the same and then there are 9 numbers which have exactly three same digits so the number of three digit numbers where exactly two digits are the same is 1000−9∗9∗8−9=343.
How many 3 digit numbers are there such that the difference between consecutive digits must be 3?
Since if the middle number is 0, the only number that differs by 3 is 3, there is thus only one possible way, 303. Since if the middle number is 9, the only number that differs by 3 is 6, there is thus only one possible way, 696.
How many three-digit positive integers can be formed from $3$?
So there are Six three-digit positive integers that can be formed from the digits $3$, $4$, and $8$. In fact, we could list them all if we really wanted to: $348, 384, 438, 483, 834, \\and 843$. The correct answer is B, $6$.
How many hundreds digit integers are there that do not contain 5?
The correct is 288. My idea is, first I get the total number of 3-digit integers that do not contain 5, then divide it by 2. And because it is a 3-digit integer, the hundreds digit can not be zero.
How many digits are left for tens place in the GRE?
Additionally, it was important to realize that we could not repeat any digits, so after using one digit in the hundreds place, then we only have two digits remaining for the tens place. Want more expert GRE prep?
https://www.youtube.com/watch?v=cGN2b76Klmo