Q. 25.0( 6 Votes )
By cross multipli
Let the required two digit number be (10x + y) where x is the digit at tens place and y is the digit at unit place.
On interchanging the digits the two digit number formed will be (10y + x).
According to the question,
y = 2x and (10y + x) = 36 + (10x + y)
⇒ 2x – y = 0 and 10x + y – 10 y – x + 36 = 0
⇒ 2x –y = 0 and 9x – 9y + 36 = 0
⇒ 2x – y = 0 and x – y + 4 = 0
On comparing with a1x + b1y + c1 = 0 and a2x + b2y + c2 = 0we get,
a1 = 2, b1 = – 1, c1 = 0; a2 = 1, b2 = – 1, c2 = 4
Applying cross multiplication method which says,
Putting the given values in the above equation we get,
∴The solution of the pair of equations is (4, 8).
So, the required two digit number will be (10x + y) = (10× 4 + 8) = 48
Rate this question :
The sum of the diGujarat Board Mathematics
By cross multipliGujarat Board Mathematics
In AABC, the measGujarat Board Mathematics
An employee deposGujarat Board Mathematics
The sum of presenGujarat Board Mathematics