in a two digit number the sum of the digit is 7 if the difference of the two digit number and the number obtained by reversing the digits is 9 then find the number
Answers
Answer:
43
Step-by-step explanation:
take the no xy. this means 10x+y( expansion form).
reverse the digits then the no is yx
yx= 10y+ x
the difference = 9x-9y
in the question the difference is given
9(x-y) = 9
so x-y =1,
sum of the digits is x+y = 7
from the 2 statement s x=4, y=3
finally the no is 43
Answer:
43
Step-by-step explanation:
Let the digits in ten's place be x and one's place be y.
Then, the original number = 10x + y.
Number obtained by reversing the digits = 10y + x.
(i)
Sum of digits is 7.
x + y = 7.
(ii)
Difference of the two digit number and number obtained by reversing is 9.
⇒ (10x + y) - (10y + x) = 9
⇒ 10x + y - 10y - x = 9
⇒ 9x - 9y = 9
⇒ x - y = 1
On solving (i) & (ii), we get
x + y = 7
x - y = 1
-------------
2x = 8
x = 4.
Substitute x = 4 in (i), we get
⇒ x + y = 7
⇒ 4 + y = 7
⇒ y = 3.
Hence, the original number = 10x + y
= 10(4) + 3
= 43.
Therefore, the original number = 43.
Hope it helps!