How many three digit numbers have the first digit equal to the sum of the other two digits

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A three digit number abc is 459 more than the sum of its digits. What is the sum of the 2 digit number ab and the 1-digit number a? (1) 71 (2) 61 (3) 51 (4) Cannot be determined

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this question there is a three digit number that is abc. So the question says that a three digit number abc is 455 59. More than the sum of its digits. You have to remind the sum of the two digit number A. B. And the one digit number A. So now the three digit number abc can be routine 100 A plus 10 B plus C, isn't it? So therefore ask for the question over here, we get 108 plus 10 B plus C. Is it going to 459 plus A plus B plus C. Right now you can just combine the items together. So we get 99 8 plus nine B is going to 459. Just divide the whole question by nine over hill. So on dividing it by nine we get 11 8 plus B is equal to 51. Let's say this is a question one. Now they were supposed to find the sum of two digit number 80 and the one digit number eight. That means you have to find out 10, 8 plus B and the one digit number eight. So this is equal to 11 A plus B. Now, if you just compare uh this equation to with the equation one, you'll find, this is see that means the sum of the two digit number 80 and one digit number is equal to 15. 151 is still answer. That means option three is the correct choice over here.

One answer says $126$, the other $135$. Which one is correct?

Brute-forcing in Haskell,

λ filter (\(a,b,c)->(a+b==c || a+c==b || b+c==a)) [ (x2,x1,x0) | x0 <- [0..9], x1 <- [0..9], x2 <- [1..9] ]
[(1,1,0),(2,2,0),(3,3,0),(4,4,0),(5,5,0),(6,6,0),(7,7,0),(8,8,0),(9,9,0),(1,0,1),(2,1,1),(1,2,1),(3,2,1),(2,3,1),(4,3,1),(3,4,1),(5,4,1),(4,5,1),(6,5,1),(5,6,1),(7,6,1),(6,7,1),(8,7,1),(7,8,1),(9,8,1),(8,9,1),(2,0,2),(1,1,2),(3,1,2),(4,2,2),(1,3,2),(5,3,2),(2,4,2),(6,4,2),(3,5,2),(7,5,2),(4,6,2),(8,6,2),(5,7,2),(9,7,2),(6,8,2),(7,9,2),(3,0,3),(2,1,3),(4,1,3),(1,2,3),(5,2,3),(6,3,3),(1,4,3),(7,4,3),(2,5,3),(8,5,3),(3,6,3),(9,6,3),(4,7,3),(5,8,3),(6,9,3),(4,0,4),(3,1,4),(5,1,4),(2,2,4),(6,2,4),(1,3,4),(7,3,4),(8,4,4),(1,5,4),(9,5,4),(2,6,4),(3,7,4),(4,8,4),(5,9,4),(5,0,5),(4,1,5),(6,1,5),(3,2,5),(7,2,5),(2,3,5),(8,3,5),(1,4,5),(9,4,5),(1,6,5),(2,7,5),(3,8,5),(4,9,5),(6,0,6),(5,1,6),(7,1,6),(4,2,6),(8,2,6),(3,3,6),(9,3,6),(2,4,6),(1,5,6),(1,7,6),(2,8,6),(3,9,6),(7,0,7),(6,1,7),(8,1,7),(5,2,7),(9,2,7),(4,3,7),(3,4,7),(2,5,7),(1,6,7),(1,8,7),(2,9,7),(8,0,8),(7,1,8),(9,1,8),(6,2,8),(5,3,8),(4,4,8),(3,5,8),(2,6,8),(1,7,8),(1,9,8),(9,0,9),(8,1,9),(7,2,9),(6,3,9),(5,4,9),(4,5,9),(3,6,9),(2,7,9),(1,8,9)]

λ length $ filter (\(a,b,c)->(a+b==c || a+c==b || b+c==a)) [ (x2,x1,x0) | x0 <- [0..9], x1 <- [0..9], x2 <- [1..9] ]
126

If $x_2 = 0$ is allowed, then

λ filter (\(a,b,c)->(a+b==c || a+c==b || b+c==a)) [ (x2,x1,x0) | x0 <- [0..9], x1 <- [0..9], x2 <- [0..9] ]
[(0,0,0),(1,1,0),(2,2,0),(3,3,0),(4,4,0),(5,5,0),(6,6,0),(7,7,0),(8,8,0),(9,9,0),(1,0,1),(0,1,1),(2,1,1),(1,2,1),(3,2,1),(2,3,1),(4,3,1),(3,4,1),(5,4,1),(4,5,1),(6,5,1),(5,6,1),(7,6,1),(6,7,1),(8,7,1),(7,8,1),(9,8,1),(8,9,1),(2,0,2),(1,1,2),(3,1,2),(0,2,2),(4,2,2),(1,3,2),(5,3,2),(2,4,2),(6,4,2),(3,5,2),(7,5,2),(4,6,2),(8,6,2),(5,7,2),(9,7,2),(6,8,2),(7,9,2),(3,0,3),(2,1,3),(4,1,3),(1,2,3),(5,2,3),(0,3,3),(6,3,3),(1,4,3),(7,4,3),(2,5,3),(8,5,3),(3,6,3),(9,6,3),(4,7,3),(5,8,3),(6,9,3),(4,0,4),(3,1,4),(5,1,4),(2,2,4),(6,2,4),(1,3,4),(7,3,4),(0,4,4),(8,4,4),(1,5,4),(9,5,4),(2,6,4),(3,7,4),(4,8,4),(5,9,4),(5,0,5),(4,1,5),(6,1,5),(3,2,5),(7,2,5),(2,3,5),(8,3,5),(1,4,5),(9,4,5),(0,5,5),(1,6,5),(2,7,5),(3,8,5),(4,9,5),(6,0,6),(5,1,6),(7,1,6),(4,2,6),(8,2,6),(3,3,6),(9,3,6),(2,4,6),(1,5,6),(0,6,6),(1,7,6),(2,8,6),(3,9,6),(7,0,7),(6,1,7),(8,1,7),(5,2,7),(9,2,7),(4,3,7),(3,4,7),(2,5,7),(1,6,7),(0,7,7),(1,8,7),(2,9,7),(8,0,8),(7,1,8),(9,1,8),(6,2,8),(5,3,8),(4,4,8),(3,5,8),(2,6,8),(1,7,8),(0,8,8),(1,9,8),(9,0,9),(8,1,9)

λ length $ filter (\(a,b,c)->(a+b==c || a+c==b || b+c==a)) [ (x2,x1,x0) | x0 <- [0..9], x1 <- [0..9], x2 <- [0..9] ]
136

Even if we remove $000$ from the list, which would give $135$ numbers, $011$ is not a $3$-digit number.

How many three

How many 3 digit numbers can be formed from the digits 1 2?

How many possible 3 digit numbers are there where all of the digits are different?

How many 3 digit numbers can be formed using all the 3 digits 1/2 and 3?