Solve (8:4:2)-3-1: Order of Operations with Sequential Division

Sequential Division with Negative Results

(8:4:2)31= (8:4:2)-3-1=

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Solve the following problem
00:03 Always solve the parentheses first
00:07 Solve the expression according to the order of operations, solve from left to right
00:17 Use the commutative law and arrange in a way that's convenient to solve
00:21 This is the solution

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

(8:4:2)31= (8:4:2)-3-1=

2

Step-by-step solution

According to the rules of the order of operations, we first solve the exercise within parentheses from left to right:

8:4=2 8:4=2

2:2=1 2:2=1

Now we get the exercise:

131= 1-3-1=

We solve the exercise from left to right:

13=2 1-3=-2

21=3 -2-1=-3

3

Final Answer

3-

Key Points to Remember

Essential concepts to master this topic
  • Parentheses First: Solve operations inside parentheses completely before moving outside
  • Left-to-Right: Sequential division 8:4:2 8:4:2 means (8:4):2=2:2=1 (8:4):2 = 2:2 = 1
  • Check Final Answer: Verify 131=21=3 1-3-1 = -2-1 = -3

Common Mistakes

Avoid these frequent errors
  • Solving division operations out of order
    Don't solve 8:4:2 8:4:2 as 8:(4:2)=8:2=4 8:(4:2) = 8:2 = 4 = wrong result of 1! This violates left-to-right order and changes the mathematical meaning. Always solve sequential operations from left to right within parentheses.

Practice Quiz

Test your knowledge with interactive questions

\( 94+12+6= \)

FAQ

Everything you need to know about this question

Why do we solve from left to right in the parentheses?

+

Division and multiplication have the same priority level, so when they appear together, we solve from left to right. Think of 8:4:2 8:4:2 as two separate steps: first 8:4=2 8:4 = 2 , then 2:2=1 2:2 = 1 .

What if I solved the subtraction from right to left?

+

Subtraction must also go left to right! If you do 1(31)=12=1 1-(3-1) = 1-2 = -1 instead of (13)1=21=3 (1-3)-1 = -2-1 = -3 , you'll get the wrong answer because subtraction isn't associative.

How do I remember PEMDAS with negative numbers?

+

Use PEMDAS normally, but be extra careful with negative signs. When you get 13=2 1-3 = -2 , that negative stays with the 2 in the next step: 21=3 -2-1 = -3 .

Is there a difference between : and ÷ symbols?

+

No difference at all! Both : and ÷ mean division. Some countries prefer one symbol over the other, but they work exactly the same way in calculations.

Can I check my work a different way?

+

Yes! You can substitute back: if the answer is 3 -3 , then (8:4:2)31 (8:4:2)-3-1 should equal 131=3 1-3-1 = -3 ✓. You can also use a calculator to verify each step.

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Commutative, Distributive and Associative Properties questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations