Question

Seven times a two-digit number is equal to four times the number obtained by reversing the order
of its digit. If the difference between the digits is 3, then find the number.
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Answer 1

Step-by-step explanation:

Let numbers be x at ones place and y at tens place so

10y+x is that digit

now reversed digit is 10x+y

according to question

7 (10y+x)=4(10x+y)

x=2y (i)

now

given

x-y=3

from eq. i 2y=x

2y-y=3

y=3

so

x=63

required original no. is 36 and reversed digit is 63

Answer 2

Answer:

36

Step-by-step explanation:

Let the unit digit be a and tenth unit be b .

So , number = 10 b + a

It's said number is seven times is equal to reversing the order of its digit.

= > 7 ( 10 b + a ) = 4 ( 10 a + b )

= > 70 b + 7 a = 40 a + 4 b

= > 66 b = 33 a

= > a = 2 b ... ( i )

Also given numbers' difference is 3 .

a - b = 3  ( ii )

From ( i ) and ( ii ) we get :

a b - b = 3

b = 3

= > a = 6

Hence number = > 30 + 6

= > 36.