(10A+B)(10C+D)= 100AC+10AD+10BC+BD
(10A+B)(10D+C)= 100AD+10BD+10AC+BC
subtract 2nd frm 1st
d= 9(C-D)(10A+B)
d shld be divisible by 9, so option a,b gone(sum is nt divisbl by 9)
max(d) = 9(9-0)(10.9+9) = 8019 so option d gone
hence only option left c
therfore option(c)
Whats the OA?
ash_paglaguy SaysIs the answer a^2/4..
barclays_boss Saysif a n degree equation has n+1 roots...then what can we say about the nature of the equation?.....for eg. if a quadratic equation happens to have three roots
When you reverse the digits of the number 13, the number increases by 18. How many other two-digit numbers increase by 18 when their digits are
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