Solve this: Q (1) How many numbers of 4 digits can be formed by using the digits 1, 2, 3, - Maths -

Question

Solve this:
Q (1) How many numbers of 4 digits can be formed by using the
digits 1, 2, 3, 4, 5, 6, 7 if no digit is repeated in any number?
How many of these numbers are
(a) divisible by 2, (b) greater than 3400?

Varun Rawat · Accepted Answer

No
 of ways to fill units place = 7No
 of ways to fill tens place = 6No
 of ways to fill hundreds place = 5No
 of ways to fill thousands place = 4Total number of 4-digit number that an be formed = 7 × 6 × 5 × 4 = 840a
For a number to be divisible by 2, we must have 2, 4 or 6 in units place
No
 of ways to fill units place = 3No
 of ways to fill tens place = 4No
 of ways to fill hundreds place = 3No
 of ways to fill thousands place = 2Total number of required numbers = 3×4×3×2= 72
Kindly ask the remaining part in different thread

Solve this: Q.(1) How many numbers of 4 digits can be formed by using the digits 1, 2, 3, 4, 5, 6, 7 if no digit is repeated in any number? How many of these numbers are (a) divisible by 2, (b) greater than 3400?

Solve this:
Q.(1) How many numbers of 4 digits can be formed by using the digits 1, 2, 3, 4, 5, 6, 7 if no digit is repeated in any number? How many of these numbers are
(a) divisible by 2, (b) greater than 3400?