use the additive inverse to find -123.45 - ( -234.76)

A. -358.21
B. 111.31
C. -111.31
D. 121.31

1 answer

To solve \(-123.45 - (-234.76)\), we can use the additive inverse property. The additive inverse of a number is the opposite of that number. Thus, \(-(-234.76)\) becomes \(+234.76\).

Now we can rewrite the expression:

\[ -123.45 + 234.76 \]

Now we perform the addition:

\[ 234.76 - 123.45 \]

To compute this, we can line up the numbers vertically:

  234.76
- 123.45
_________

Subtracting:

  • From 6, we can't subtract 5, so we borrow 1 from the 7 (turning it into a 6), making 16.
  • \(16 - 5 = 11\), so we write down 1 and carry over 1.
  • From 6 (now 6 after borrowing), subtract 4: \(6 - 4 = 2\).
  • Next, we have 4 (originally 3, but we borrowed 1) and we subtract 3: \(4 - 3 = 1\).
  • Moving on, \(2 - 2 = 0\).
  • Finally, \(2 - 0 = 2\).

Putting it all together, we have:

  234.76
- 123.45
_________
  111.31

Thus, \(-123.45 - (-234.76) = 111.31\).

So the correct answer is:

B. 111.31