take option 1: x=3 and y=1 means 9471×9y2 becomes 94713912 9+4+7+1+x+9+y+2=32+x+y=32+3+1=36 is divisble by 9 Last three digits 912 is also divisible by 8 Hence, Divisble by 72 take option 2: x=8 and y=5 means 9471×9y2 becomes 94718952 9+4+7+1+x+9+y+2=32+x+y=32+8+5=45 is divisble by 9 Last three digits 952 is also divisible by 8 Hence, Divisble by 72 take option 3: x=4 and y=9 means 9471×9y2 becomes 94714992 9+4+7+1+4+9+9+2=32+x+y=32+4+9=45 is divisble by 9 Last three digits 992 is also divisible by 8 Hence, Divisble by 72 take option 4: x=9 and y=5 means 9471×9y2 becomes 94719952 9+4+7+1+9+9+5+2=32+x+y=32+9+5=46 is not divisble by 9 Last three digits 952 is also divisible by 8 Hence, Not Divisble by 72 Hence, The Correct option is option 4.