A four digit number having all digit successive when substracted by the number formed by using all t

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15 Oct 2015 Four digit number

A four digit number having all digit successive when substracted by the number formed by using all the digits in reverse pattern (ie reverse of xyz is zyx) gives a four digit number. The sum of all digits of that number is 18. What will be the product of thousand and units digit of that number

OPtion

1) 0
2) 6
3) 8
4) 18
5) 21
6) 24
7) 30
8) 42
9) 54
10)56

Solution

Let number is 1000x + 100y + 10z + p (i)
its reverse number will be 1000p + 100z + 10y + x (ii)
(ii) - (i) = 999p + 90z - 90y - 999x
999(p-x) + 90(z-y)
999*3 + 90*1 = 2997+90 = 3087
21

Option 5)

Correct Option: 5 Best Solution (9)

bhaskar   9 years AGO

1000(x+3-x)+100(x+2-x-1)+10(x+1-x-2)+(x-x-3)=3087
ans:3*7=21

Like? Yes (5) | No   

Vishal Kumar   9 years AGO

let the digit is 8765 - 5678 =3087 =>3+0+8+7=18
so 3*7=21. Answer is 21

Like? Yes (4) | No   

Meenakshi   9 years AGO

A Four digit number is 3456
Reverse of that number= 6543
=>6543-3456 = 3087
Sum of all digits = 18
3+0+8+7 = 18
so product of thousand and unit digit = 3*7=21
option 5)

Like? Yes (2) | No   

M Narasimhulu   9 years AGO

4321
-1234
3087
21

Like? Yes (1) | No   

MRITUNJAY   9 years AGO

the number is 6543
reverse is 3456
diff = 3087
product is 21

Like? Yes (1) | No   

Robert Yogenson   9 years AGO

suppose digit like=6543
and reverse digit=3456
subtract=6543-3456=3087
and total of 3+0+8+7=18(condition fallow )
then output will be 3X7=21
if you choose another digit then digit will be 7654 and etc

Like? Yes (1) | No   

Satya Samhitha Papineni   9 years AGO

the difference between any four digit number having all digits successive and a number formed by reversing it is 3087
so the product is 21

Like? Yes (1) | No   

harshavi   9 years AGO

by trial method we can guess that the digits should be 3,4,5,6.
so the number should be 6543
by substracting with the reverse of that number w get
6543-3456=2087.
the product of thousands and units digit would be 21

Like? Yes (1) | No   

ABHINAV PUSHPAM   9 years AGO

The number will be 3456. Its reverse will be 6543. Their difference will be 3087. so product of 3*7=21
option 5)

Like? Yes (1) | No (1)