Q(2.) The sum of the digits of a 2-digit number is 7. If the digits are reversed, the new number increased by 3
less than 4 times the original number. Find the original number.
Q(3.) The sum of a number of 2 digits and of the number formed by reversing the digits is 110, and the difference
of the digits is 6. Find the number.
PLEASE FAST.
I WILL MARK THE ANSWER AS BRAINLIST.
Answers
Step-by-step explanation:
Q2:- Let the digits of the number be x and y respectively .
Then we know the number is of the form 10x + y
Reversing the digits of the number makes the number of the form 10y + x
Also x + y = 7
So we can say x = 7 - y
And we know :- 4(10x + y) - 3 = 10y + x as given
So:- 40x + 4y - 3 = 10y + x
=> 40(7 - y) + 4y - 3 = 10y + (7 - y)
=> 280 - 40y + 4y - 3 = 7 + 9y
=> 270 = 45y
=> y = 6
Hence From x = 7 - y , we get x = 7 - 6 = 1
So the original number is 16 and the new number is 61 .
Q3:- Let the digits of the number be x and y respectively .
Then the number is of the form 10x + y
Reversing the number gives 10y + x .
First we assume if x > y .
Then x - y = 6
So I can say x = 6 + y
And we know:- (10x + y) + (10y + x) = 110
=> 10(6 + y) + y + 10y + (6 + y) = 110
=> 60 + 10y + y + 10y + 6 + y = 110
=> 22y + 66 = 110
=> 22y = 176
=> y = 8
Hence from x = 6 + y , we get x = 6 + 8 = 14
But that is not possible since x cannot be 2-digit number .
Since we first assumed x>y , our assumption was wrong .
So y>x , and y - x = 6
This gives x = 2
So the original number is 82 and reversing the number gives 28 .