there is number X in decimal represntation whose last digit
is not 0. if digits of X are reversed then we obtain new
number say Y. both X and Y are divisible by 7. then find
all such X from 10 to 1000.
Answer Posted / sanchit
consider any 3 digit number first...
100a+10b+c
reverse it-
100c+10b+a
if these two numbers are divisible by 7 even their
difference must be
so
99(a-c) is div by 7
-> a-c=7n
c can't be 0
so possible combinations-
8,1(you can also consider n=0 ->a=c)
and 9,2 ->numbers- 952,259,861,168(palindromes-707,77,868,777)
Is This Answer Correct ? | 7 Yes | 0 No |
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