Question

Seven times a given two digit number is equal to four times the number obtained by interchanging the digits and the diffeence of the digit is three. find the number

Answer 1

Answer:

36

Step-by-step explanation:

let the number at units place be x and number at tens place be y

now original numbe r = 10y +x

reversed number = 10x+y

now as per given condition

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

70y+ 7x=40x+4y

66y=33x

dividin both side by 33 we get

2y=x

also

x-y=3

putting x=2y

we get y=3

so x=6

so the nmber is 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 :

2 b - b = 3

b = 3

= > a = 6

Hence number = > 30 + 6

= > 36.