Question

I am a 3 digit positive number. The sum of my digits is 18. My middle digit is the product of -2 and -4. My first digit is 3^2.

Answer 1

Hi! ⋇

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The first digit of this number is 3², which is 9.

The Number is : 9xx

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The second digit is: -2·(-4)=8.

The Number is : 98x.

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The sum of all the digits is 18. This gives us an equation that we can solve in terms of x!

$\multimap\sf{9+8+x=18}$ (x is the digit we are looking for)

Now it takes a little arithmetic to find x :)

$\multimap\sf{17+x=18}$. Just subtract 17 from both sides to find x!

$\multimap\sf{x=1}$. And Now, can you see the number!

It's 981, of course :)

Hope this made sense to you!

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$\large\it{\overbrace{Calligrxphy}}$

Answer 2

Let x be the first digit.
Let y be the second digit.
Let z be the third digit.

x+y+z=18

y= (-2)(-4)
y= 8

x= 3^2
x= 9

Therefore z=1.

The number is
= 100x+10y+z
= 100(9)+10(8)+(1)
= 981