The sum of digit of a two digit number is 10.if inter changing the digit,the new number is 18 more than the original number.what will be the original number?
Answers
Original Number = 64
Step-by-step explanation:
Given:
Sum of a two digit number is 10.
After interchanging digits the new number formed is 18 less than original.
To Find:
What is the original number ?
Solution: Let the tens digit he x and ones digit be y. Therefore, number is 10x + y.
➟ Tens + Ones = 10
x + y = 10 or
x = (10 – y)......(1)
[ Now, interchanging the digits of the number ]
New number formed is 10y + x
A/q
After interchanging digits the new number formed is 18 less than original.
⟹ 10x + y = 10y + x – 18
⟹ 10x – x = 10y – y – 18
⟹ 9x = 9y – 18
⟹ 9x – 9y = – 18
⟹ 9(x – y) = – 18
⟹ x – y = 2
⟹ (10 – y) – y = 2
⟹ – 2y = 2 – 10
⟹ – 2y = – 8
⟹ y = 8/2 = 4
So, the digits of number is
• Ones digit is y = 4
• Tens digit is x = 10 – 4 = 6
Hence, the original number is 10(6) + 4 = 64