Question

seven times two digits number is equal to four times the number obtained by reversing the order of their digits.find the number if the difference between its digits is three

Answer 1

7(10x+y)=4(10y+x)
70x+7y=40y+4x
66x=33y
2x=y
And
y-x=3
2x-x=3
x=3
y=6
Number=36

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.