Insert the correct sequence of operations between 7, 4, 8, 2 to make 24: 7 ? 4 ? 8 ? 2 = 24 (standard precedence applies)

Difficulty: Easy

Correct Answer: x, - and ÷

Explanation:


Introduction / Context:
We must choose a specific ordered trio of operations to place between 7, 4, 8, 2 so that the resulting expression equals 24. Standard operator precedence (× and ÷ before + and −) must be respected.


Given Data / Assumptions:

  • Numbers in order: 7, 4, 8, 2.
  • We pick one of the provided ordered triples of operators and apply normal precedence.


Concept / Approach:
Try options mentally while honoring precedence. Multiplication early tends to raise the value, and a final subtraction after a division can fine-tune to 24.


Step-by-Step Solution:

Option (c): 7 × 4 − 8 ÷ 2. Compute ÷ and × first: 7 × 4 = 28; 8 ÷ 2 = 4. Then subtract: 28 − 4 = 24 ✔.


Verification / Alternative check:
Test other options quickly:

  • 7 − 4 × 8 × 2 = 7 − 64 = −57 ✘
  • 7 − 4 × 8 ÷ 2 = 7 − 16 = −9 ✘
  • 7 × 4 ÷ 8 − 2 = 3.5 − 2 = 1.5 ✘


Why Other Options Are Wrong:
They either ignore precedence or yield values far from 24 when computed correctly with precedence.


Common Pitfalls:
Evaluating strictly left-to-right or misordering ×/÷ versus +/−, which changes the outcome.


Final Answer:
x, - and ÷ (i.e., 7 × 4 − 8 ÷ 2 = 24).

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