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Order of operations with negative numbers
Order of operations 256
Description
Exercise Name: Order of operations with negative numbers
Math Missions: 7th grade (U.S.) Math Mission, Pre-algebra Math Mission, Algebra basics Math Mission, Mathematics I Math Mission
Types of Problems: 1

The Order of operations with negative numbers exercise appears under the 7th grade (U.S.) Math Mission, Pre-algebra Math Mission, Algebra basics Math Mission and Mathematics I Math Mission. This exercise uses the order of operations (PEMDAS) on problems with negative numbers.

Types of Problems[]

There is one type of problem in this exercise:

  1. Use order of operations to evaluate: This problem has a numerical expression that makes use of many operation and types of numbers, including negatives. Users are asked to evaluate the expression correctly and provide the answer in the space provided.
    Oownn1

    Use order of operations to evaluate

Strategies[]

Knowledge of PEMDAS is needed to complete this problem correctly for getting accuracy badges and speed badges.

  1. The order if operations are to do operations inside parentheses first, followed by exponents (and possibly radicals), then multiplication and division in order from left to right, and finally addition and subtraction in order from left to right.
  2. PEMDAS is an acronym to remember the order of operations, but it can be deceiving because it seems to imply that multiplication outranks division and addition outranks subtraction.
  3. "Please excuse my dear Aunt Sally" is another mnemonic to help remember the order of operations.
  4. The order of operations is determined by the fact that addition (and it's inverse operation subtraction) are the simplest operations. Multiplication and division are repeated addition and subtraction respectively. Finally, exponentiation is repeated multiplication (which in turn is repeated addition).

Real-life Applications[]

  1. Order of operations are sometimes needed in computer programming because some expressions may not be solved properly.
  2. Negative numbers are used to represent land below sea level.
  3. Negative numbers are used to describe values on a scale that goes below zero, such as the Celsius and Fahrenheit scales for temperature.