A four digit number is to be formed using the digits 1 to 7
All digits of the number are different and repetition is not
allowed.
1. How many such numbers can be formed ?
2. How many such numbers are divisible by 4 ?

Answer Posted / hh

I see with 1..7 if last 2 digits are
12,16,24,32,36,52,56,64,72,76...then the no. is divisible by 4

means last 2 digits has possible 10 Combinations

So Answer=P(5,2)*10=20*10=200

its correct!!!!!!!!!!!!!

Is This Answer Correct ?    6 Yes 0 No



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