Solve (40+70+35-7)×9: Order of Operations Practice

Order of Operations with Parentheses First

(40+70+357)×9= (40+70+35-7)\times9=

❤️ 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
00:06 Given that there is only addition/subtraction, solve from left to right
00:10 Each time solve the 2 leftmost terms
00:22 Now that we have solved the parentheses we can proceed to multiply
00:26 This is the solution

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

(40+70+357)×9= (40+70+35-7)\times9=

2

Step-by-step solution

We simplify this expression by observing the order of arithmetic operations which states that exponentiation precedes multiplication, division precedes addition and subtraction, and that parentheses precede everything else.

Therefore, we first start by simplifying the expression within the parentheses. We then multiply the result of the expression within the parentheses by the term that multiplies it:

(40+70+357)9=1389=1242 (40+70+35-7)\cdot9= \\ 138\cdot9=\\ 1242 Therefore, the correct answer is option C.

3

Final Answer

1242

Key Points to Remember

Essential concepts to master this topic
  • Rule: Parentheses always come first before multiplication or division
  • Technique: Calculate 40+70+35-7 = 138, then multiply by 9
  • Check: Verify 138 × 9 = 1242 by breaking into 130×9 + 8×9 ✓

Common Mistakes

Avoid these frequent errors
  • Multiplying before completing parentheses
    Don't multiply 9 by individual terms like 40×9 + 70×9 = wrong approach! This ignores the parentheses and creates a much harder problem. Always complete everything inside parentheses first, then multiply the result.

Practice Quiz

Test your knowledge with interactive questions

\( 140-70= \)

FAQ

Everything you need to know about this question

Why can't I just multiply 9 by each number separately?

+

Because the parentheses group everything together first! When you see (40+70+35-7)×9, the parentheses mean 'add and subtract these numbers first, then multiply the total by 9.'

What's the easiest way to add 40+70+35-7?

+

Add the positive numbers first: 40+70+35 = 145, then subtract: 145-7 = 138. This keeps the arithmetic simple and reduces mistakes.

How do I multiply 138 × 9 without a calculator?

+

Break it down:

  • 130 × 9 = 1170
  • 8 × 9 = 72
  • 1170 + 72 = 1242

What if I forgot to do parentheses first?

+

You'll get the wrong answer! For example, doing 40×9 first gives 360, but the correct answer is 1242. Always remember: parentheses come before everything else.

Is there a memory trick for order of operations?

+

Yes! Remember PEMDAS: Parentheses, Exponents, Multiplication/Division (left to right), Addition/Subtraction (left to right). Some say 'Please Excuse My Dear Aunt Sally!'

🌟 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