the sum of two digit number is 11. if you subtract 27 from the number the digits are reversed . what is the number
Answers
The Number is 74
Given :
Sum of the Digits of the Number = 11
If 27 is subtracted from the number the digits are reversed.
To Find :
The Numbers
Solution :
- Units Place = x
- Tens Place = 10(11 - x)
◆
10(11 - x) + x
110 - 10x + x
110 - 9x ..... [ Original Number ]
◆
If 27 is subtracted from the number the digits are reversed.
◆
- Units Place = 11 - x
- Tens Place = 10(x)
★
(110 - 9x) - 27 = 10x + 11 - x
110 - 27 - 9x = 10x - x + 11
83 - 9x = 9x + 11
-9x - 9x = 11 - 83
-18x = -72
18x = 72
x = 72/18
x = 4
Units Place = 4
★ Value of 10(11 - x)
10(11 - 4)
10(7)
70
Tens = 70
◆
- Units Place = 4
- Tens = 70
Number = 70 + 4 = 74
The Number is 74
Subtract 27 from 74
74 - 27
47
47 has reversed digits of 74.
The Number is 74
Answer :-
The number is 74
Solution :-
Let the two digits of a two digit number be x and y
Sum of two digits of a two digit number = 11
x + y = 11
y = 11 - x ---- (1)
Original number = 10(x) + y = 10x + (11 - x) = 10x + 11 - x = 9x + 11
Number when digits are reversed = 10(y) + x = 10(11 - x) + x = 110 - 10x + x = 110 - 9x
Given
Original number - 27 = Number when digits are reversed
(9x + 11) - 27 = 110 - 9x
9x + 11 - 27 = 110 - 9x
9x - 16 = 110 - 9x
9x + 9x = 110 + 16
18x = 126
x = 126/18
x = 7
Therefore Ten's place = 7
Substitute x = 7 in (1)
y = 11 - x
y = 11 - 7
y = 4
Now to find the number substitute value of x in 9x + 11
9x + 11
= 9(7) + 11
= 63 + 11
= 74