Post 3: Are You Ready? Order of Operations

Sage peers into the new room to sees a chamber hooked up to a mess of cables. The cables all seem to connect to a door on the far end of the room. chambers. The kids keep their distance as sage approaches. As he gets closer, he notices there are chambers within the chambers, one has a parentheses, one has an exponent, one has a multiplication and division sign, and the innermost has a plus and minus sign. Sage opens the door and discovers that there are controls within each chamber. Sage goes to the innermost one and pushes a button, and is instantly teleported back outside the machine. Sage sees the kids looks dismayed, as though they have all had this happen. But Sage is undeterred.

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Do you know what the Order of Operations is?

It tells you what order to do math when you get a big equation like this:

5³ + 8 ⋅ (2 / 4 - 10)

There is a helpful acronym that makes remembering this order much simpler.

PEMDAS

P (Parentheses)

E (Exponents) - (if you need a refresher on exponents, click here)

M (Multiplication)

D (Division)

A (Addition)

S (Subtraction)

The way this works is you do:

Parentheses before Exponents

Exponents before Multiplication and Division

Multiplication and Division before Addition and Subtraction.

There is, however, a single pitfall of this memorization method.

This being, the final 4 case come in equal groups of 2.

Essentially, Multiplication and Division come at the same time as each other.

And Addition and Subtraction also come at the same times as each other.

So lets look at the original problem again.

Lets do an example to understand the pitfall I talked about earlier

This same logic also applies to Addition and Subtraction

So remember, if you come across lots of things to do, use PEMDAS.

But you should try a practice problem to make sure you remember this.

This scratch pad will correct you as you work

Sage uses the order of operations to turn on the chambers in the correct order. The kids all look up, amazed as they see the whole machine whir to life, energy pulsing through the cables. Beautiful lights illuminate the room, and Sage notices a small gate opens in a corner, barely larger than a kid. He leads the group towards it....

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