The sum of the digits of a two-digit number is 8. If 16 is added to the original number, the result is 3 times the original number with its digits reversed. Find the original number.
I'll explain how I got it.....
So I focused on the numbers that have their digits as a sum of 8 first
8,17,26,35,44,53,62,71,80
I added 16+8=24
You know CPhill?!?! 8 is also correct!!!! There is nothing to swap....unless you put a 0 at the beginning, which I never do
17+16=33
71 is the swapped 17
26+16=42
62 is the swapped 26
35+16=51
53 is the swapped 35
44+16=60
44 is the swapped 44
53+16=69
35 is the swapped 53
62+16=78
26 is the swapped 62
71+16=89
17 is the swapped 71
80+16=96
8 is the swapped 80
First time around....I stared at my work and saw well 26*3=78 so that's the only answer
Now I see 8 could be correct too!!!!
The sum of the digits of a two-digit number is 8. If 16 is added to the original number, the result is 3 times the original number with its digits reversed. Find the original number.
Let x be the first digit and y be the second digit.....so we have......
x + y = 8 (1)
And the original numbe can be represented as 10x + y
And we have
10x + y + 16 = 3(10y + x)
And using (1) we have that y = 8 - x
So we have
10x + (8 - x) + 16 = 3[10(8-x) + x]
9x + 8 + 16 = 3 [[80 - 10x -+ x]
9x + 24 = 3 [ 80 - 9x ]
9x + 24 = 240 - 27 x subtract 24 from both sides and add 27x to both sides
36x = 216
So....x = 6 and y = [8 - x ] → [8 - 6] = 2
So the original number is 62
And adding 16 to this = 78
And this is 3 times the original number with the digits reversed, i. e., 26 * 3 = 78
You're correct, happy7, but we need to see some math.......nobody will be able to figure out how you got your answer, otherwise.......
I'll explain how I got it.....
So I focused on the numbers that have their digits as a sum of 8 first
8,17,26,35,44,53,62,71,80
I added 16+8=24
You know CPhill?!?! 8 is also correct!!!! There is nothing to swap....unless you put a 0 at the beginning, which I never do
17+16=33
71 is the swapped 17
26+16=42
62 is the swapped 26
35+16=51
53 is the swapped 35
44+16=60
44 is the swapped 44
53+16=69
35 is the swapped 53
62+16=78
26 is the swapped 62
71+16=89
17 is the swapped 71
80+16=96
8 is the swapped 80
First time around....I stared at my work and saw well 26*3=78 so that's the only answer
Now I see 8 could be correct too!!!!