Equal Shares
Part of the Numbers & Operations section of Coddy's Pre-Algebra journey. Lesson 54 of 60.
Three friends run up a debt of 45 dollars and agree to share it equally. The debt is a negative amount, -45, and sharing equally means dividing. Use s for share: s = -45 / 3. A negative divided by a positive is negative, so the next line is s = -15. Each friend owes 15 dollars.
The sign makes sense: splitting a debt gives smaller debts, not money. Multiplying goes the other way round. Three shares of -15 put back together are 3 × (-15), which is -45, the whole debt.
That reverse step is also how you check a share: multiply it by the number of people and you should get the total you started with, sign included.
Challenge
Four friends share a debt of 84 dollars equally. Find each friend's share s as a signed number (a debt is negative). Write s equal to the calculation, then work it down to one number.
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Numbers & Operations
1Working on the Board
Your First AnswerType the Next LineOne Line at a TimeDots and BarsFriendly ProductsRecap: Board Work4Adding Integers
Adding Two NegativesDifferent SignsZero PairsAdding Several IntegersRecap: Adding Integers2Order of Operations
Multiply Before AddingLeft to RightParentheses FirstBrackets Inside BracketsThe Fraction Bar GroupsRecap: Order of Operations5Subtracting Integers
Add the OppositeSubtracting a NegativePlus and Minus in a RowDistance Between NumbersRecap: Subtracting Integers