Q. How many numbers divisible by 5 and lying between 3000 and 4000 that can be formed from the digits 1, 2, 3, 4, 5, 6 (repetition of digits is not allowed)?
A) $\ ^{6}P_{2}$
B) $\ ^{5}P_{2}$
C) $\ ^{4}P_{2}$
D) $\ ^{6}P_{3}$
Explanation
(c)
In the number which is divisible by 5 and lying between 3000 and 4000, 3 must be at thousand place and 5 must be at unit place. Therefore rest of the digits (1, 2, 3, 4, 6) fill in two places. The number of ways=$\ ^{4}P_{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.