Question

tobie is estimating the sum of the expression -50+51. which reasoning would lead tobie to the right answer? -50 + 50 is equal to -100 plus -1 is -101. -50 + 50 is equal to zero plus -1 is -1. -50 + 50 is equal to zero plus 1 is 1. -50 + 50 is equal to 100 plus 1 is 101.

Explanation:

Step1: Analyze -50 + 50

Recall that a number and its opposite sum to zero. So, \(-50 + 50 = 0\).

Step2: Analyze the remaining term in -50 + 51

The expression \(-50 + 51\) can be rewritten as \((-50 + 50) + 1\). We already found that \(-50 + 50 = 0\), so substituting that in, we get \(0 + 1 = 1\). Now we check each option:

• First option: \(-50 + 50\) is not -100, and adding -1 is incorrect.
• Second option: After \(-50 + 50 = 0\), we should add 1, not -1.
• Third option: Matches our calculation: \(-50 + 50 = 0\) and \(0 + 1 = 1\).
• Fourth option: \(-50 + 50\) is not 100, and adding 1 is incorrect.

Answer:

\(-50 + 50\) is equal to zero plus 1 is 1.