Advertisements
Advertisements
Question
How many numbers are there between 99 and 1000 having 7 in the units place?
Advertisements
Solution
First note that all these numbers have three digits.
7 is in the unit’s place.
The middle digit can be any one of the 10 digits from 0 to 9.
The digit in hundred’s place can be any one of the 9 digits from 1 to 9.
Therefore, by the fundamental principle of counting
There are 10 × 9 = 90 numbers between 99 and 1000 having 7 in the unit’s place.
APPEARS IN
RELATED QUESTIONS
How many 3-digit even numbers can be formed from the digits 1, 2, 3, 4, 5, 6 if the digits can be repeated?
How many 4-letter code can be formed using the first 10 letters of the English alphabet, if no letter can be repeated?
Given 5 flags of different colours, how many different signals can be generated if each signal requires the use of 2 flags, one below the other?
How many two letter words can be formed using letters from the word SPACE, when repetition of letters is allowed?
How many two letter words can be formed using letters from the word SPACE, when repetition of letters is allowed?
How many three-digit numbers can be formed from the digits 0, 1, 3, 5, 6 if repetitions of digits are allowed?
How many three-digit numbers can be formed using the digits 2, 3, 4, 5, 6 if digits can be repeated?
How many four digit numbers will not exceed 7432 if they are formed using the digits 2, 3, 4, 7 without repetition?
Select the correct answer from the given alternatives.
A college has 7 courses in the morning and 3 in the evening. The possible number of choices with the student if he wants to study one course in the morning and one in the evening is -
How many words can be formed by writing letters in the word CROWN in different order?
Count the number of three-digit numbers which can be formed from the digits 2, 4, 6, 8 if repetitions of digits is not allowed
How many numbers are there between 100 and 500 with the digits 0, 1, 2, 3, 4, 5? if repetition of digits allowed
Count the numbers between 999 and 10000 subject to the condition that there are at least one of the digits is repeated
How many strings can be formed using the letters of the word LOTUS if the word either starts with L or ends with S?
How many strings can be formed using the letters of the word LOTUS if the word neither starts with L nor ends with S?
In how many ways 10 pigeons can be placed in 3 different pigeon holes?
Find the number of ways of distributing 12 distinct prizes to 10 students?
Find the value of 4! + 5!
Find the value of `(12!)/(9! xx 3!)`
Find the value of `(("n" + 3)!)/(("n" + 1)!)`
Evaluate `("n"!)/("r"!("n" - "r")!)` when n = 6, r = 2
Find the value of n if (n + 1)! = 20(n − 1)!
Choose the correct alternative:
In an examination there are three multiple choice questions and each question has 5 choices. Number of ways in which a student can fail to get all answer correct i
Choose the correct alternative:
The number of ways in which the following prize be given to a class of 30 boys first and second in mathematics, first and second in physics, first in chemistry and first in English is
Choose the correct alternative:
The number of 5 digit numbers all digits of which are odd i
Out of 18 points in a plane, no three are in the same line except five points which are collinear. Find the number of lines that can be formed joining the point
Find the number of positive integers greater than 6000 and less than 7000 which are divisible by 5, provided that no digit is to be repeated.
The number of possible outcomes when a coin is tossed 6 times is ______.
The number of different four-digit numbers that can be formed with the digits 2, 3, 4, 7 and using each digit only once is ______.
The sum of the digits in unit place of all the numbers formed with the help of 3, 4, 5 and 6 taken all at a time is ______.
Three letters can be posted in five letterboxes in 35 ways.
If the number of five-digit numbers with distinct digits and 2 at the 10th place is 336 k, then k is equal to ______.
The number of all four digit numbers which begin with 4 and end with either zero or five is ______.
