the sum of the digit of a 2 - digit number is11 the number obtained by interchaning the digits exceeds the original number by 27 find the number
Answers
Answer:
let no. be 10y+x
given x+y=11
x=11-y [equation 1]
after interchanging digits, new no.= 10x+y
10y+x+27= 10x+y
27= 10x-x+y-10y
27=9x-9y
27=9(x-y)
x-y= 27/9= 3
x= 3+y [equation 2]
comparing equations 1 and 2
11-y=3+y
11-3=y+y
8= 2y
y= 8/2
y= 4
from equation 2
x= 3+4
x=7
original no.= 10y+x
=40+7
=47
AnswEr :-
• Original number is 47.
Given :-
• The sum of the digit of a two digit number is 11. The number obtained by interchanging the digits exceeds the original number by 27.
To Find :-
• The original number.
SoluTion :-
Let,
• Digit at ones place be x
• Digit at tens place be 11 - x
» Original number :-
→ 10 (11 - x) + x × 1
→ 110 - 10x + x
→ 110 - 9x
» After interchanging the digits :-
→ 10x + 1 (11 - x)
→ 10x + 11 - x
→ 11 + 9x
★ New number exceeds the original number by 27.
Now,
» According to question :-
→ (9x + 11) - (110 - 9x) = 27
→ 9x + 11 - 110 + 9x = 27
→ 18x - 99 = 27
→ 18x = 99 + 27
→ 18x = 126
→ x = 126/18
→ x = 7
Original no. → 110 - 9x → 110 - 9(7) → 110 - 63 → 47