A number consists of four different digits where last digit is two times the first digit, second digit is two times the last digit and third digit at tens place is 3 less than the second digit. The difference of this four digit number and number formed by reversing its digit is:
Given, last digit is 2 times the first digit, so number can be: 1 __ __ 2 ; 2 __ __ 4 ; 3 __ __ 6 ; 4 __ __ 8
Also second digit is 2 times the last digit so we can have only two numbers from above four as other two will result into double digit at 2nd place .
.'. Remaining numbers are 1 4 __ 2 ; 2 8 __ 4
It is given that 3rd digit is 3 less than the 2nd digit, therefore, so we have numbers 1 4 1 2 and 2 8 5 4
As it is given that all four digits are different, so 1412 can not be the number and hence required number is 2854
Therefore difference of number and number formed by reversing digits = 4582 - 2854 = 1728
Correct Option 2)
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