Approximation and quick calculation: Evaluate 127.007 × 7.998 + 6.05 × 4.001 and choose the closest option.

Difficulty: Easy

Correct Answer: 1040

Explanation:


Introduction / Context:
Both products have one factor near an integer: 8 and 4. Using those nearby integers and applying small corrections yields a near-exact sum, perfect for choosing among options spaced by tens.


Given Data / Assumptions:

  • P1 = 127.007 * 7.998 ≈ 127.007 * (8 − 0.002)
  • P2 = 6.05 * 4.001 ≈ 6.05 * (4 + 0.001)


Concept / Approach:
Compute with the nearest integer then adjust by the tiny residual. Since both residuals are very small, the nearest hundred or ten remains stable.


Step-by-Step Solution:

P1 ≈ 127.007*8 − 127.007*0.002 ≈ 1016.056 − 0.254 ≈ 1015.802 P2 ≈ 6.05*4 + 6.05*0.001 = 24.2 + 0.00605 ≈ 24.206 Sum ≈ 1015.802 + 24.206 ≈ 1040.008 Closest listed option: 1040


Verification / Alternative check:
Direct calculation gives about 1040.008, confirming the chosen option.


Why Other Options Are Wrong:
1090, 1200, 1120: All are 80–160 away from the refined sum ~1040; too far for these tiny corrections.


Common Pitfalls:
Skipping the small −0.002 adjustment in the first product leads to ~1016.06, but the second product still keeps the sum very near 1040; the same nearest choice results.


Final Answer:
1040

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