Circular track 14 m wide; inner circumference 440 m:\nFind the radius of the outer circle.

Difficulty: Easy

Correct Answer: 84 m

Explanation:


Introduction / Context:
A track has uniform width. Knowing the inner circumference gives the inner radius; the outer radius is inner radius plus width.



Given Data / Assumptions:

  • Width w = 14 m.
  • Inner circumference = 440 m ⇒ 2πr_in = 440.


Concept / Approach:
r_in = 440 / (2π). Then r_out = r_in + 14.



Step-by-Step Solution:

1) Using π ≈ 22/7: r_in = 440 / (2 * 22/7) = 440 * 7 / 44 = 70 m.2) r_out = 70 + 14 = 84 m.


Verification / Alternative check:
Outer circumference would then be 2π*84 ≈ 528π/ ? Not needed; radius result is direct.


Why Other Options Are Wrong:
24, 44, 54 do not equal 70 + 14.


Common Pitfalls:
Subtracting the width instead of adding for the outer radius.


Final Answer:
84 m.

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