the sum of the digits of a two digit number is 12 . if 8 is aded to it .. the digits are reversed .find the number
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Let the digit in unit place be y and the digit in ten place be x.
If Sum of digits of two digit number is 12, then
∴ x + y = 12 ........ (i)
y = (12-x)..... (i)
Therefore the number formed is (10x + y)
If 8 is added to it, then the number will be reversed i.e
10x + y +8 = 10y + x
9x - 9y = -8............. (iii)
Put y = (12-x) in (iii)
∴9x - 9 (12-x) = -8
9x - 108 + 9x = -8.
18x = 100.
X= 100/18 = 50/9
Put x = 50/9 in (ii)
y = 12 - 50/9 = (108 - 50)/9
y = 58/9
∴Number = 10x +y
=(10 × 50/9 + 58/9)
=558/9
=62.Ans.
If Sum of digits of two digit number is 12, then
∴ x + y = 12 ........ (i)
y = (12-x)..... (i)
Therefore the number formed is (10x + y)
If 8 is added to it, then the number will be reversed i.e
10x + y +8 = 10y + x
9x - 9y = -8............. (iii)
Put y = (12-x) in (iii)
∴9x - 9 (12-x) = -8
9x - 108 + 9x = -8.
18x = 100.
X= 100/18 = 50/9
Put x = 50/9 in (ii)
y = 12 - 50/9 = (108 - 50)/9
y = 58/9
∴Number = 10x +y
=(10 × 50/9 + 58/9)
=558/9
=62.Ans.
Anonymous:
its wrong
the answer is 57
your question is already incomplete
no.... my dear friend.... its a question of linear equation in one variable
Now you see answer. I solved it by linear equation in two variable. you are wrong.
but my dear mate ansr is 57 and that is correct
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