Question

in two digit number digit at the ten' place is twice the digit at unit's place. If the number by interchanging the digits is added to the original number, the sum is 66. Find the number​

Answer 1

Answer:

The two digit number is 24.

Step-by-step explanation:

24

4 in ten's place is twice of 2 in unit's place.

24 after interchanging digits is 42.

24+42=66

Answer 2

Answer:

42

Step-by-step explanation:

let the no. at tens place be 2x

therefore,no. at ones place=x

(2x X 10) + (x X 1) = ?  -------   1

when we interchange the digits then this becomes

(x X 10) + (2x X 1) =? ---------  2

but we know the sum of 1 and 2 =66

therefore,

(2x X 10) + (x X 1) +(x X 10) + ( 2x X 1) =66

20x +x +10x+2x = 66

33x = 66

x=66/33

x = 2

therefore no. = (2x X 10) + (x X 1)

                       =(2(2) X 10) + (2 X 1)

                       =40 +2

                       =42