Problem 39

Question

Find each sum without the use of a number line. $$85+(-15)+(-20)+12$$

Step-by-Step Solution

Verified
Answer
The sum of the numbers is 62.
1Step 1: Regroup
Regroup the numbers such that the positives and negatives are together. So the given equation \(85+(-15)+(-20)+12\) will become \(85+12+(-15)+(-20)\).
2Step 2: Sum up the Positive and Negative numbers separately
The sum of the positive numbers \(85+12\) gives 97. The sum of the negative numbers \(-15+(-20)\) gives -35.
3Step 3: Add the results
Adding the results from step 2, we have: \(97+(-35)\). But adding a negative number is same as subtracting a positive number. So the expression becomes \(97-35\).
4Step 4: Solve the Expression
Solving the expression \(97-35\) gives the result 62.