Given below are two statements: Statement I: The sum of integers from 110 to…

2023

Given below are two statements:

Statement I: The sum of integers from 110 to 630 is over 300,000.

Statement II: The ratio of the circumference of a circle with its area is inversely proportional to its diameter.

In the light of the above statements, choose the most appropriate answer from the options given below:

Answer: D. Statement I is incorrect but Statement II is correctCONCEPTAn inclusive arithmetic series from a to b has n = b − a + 1 terms and sum S = n(a + b)/2. For a circle, C = 2πr, A = πr2, and d = 2r; proportionality…

  1. A.

    Both Statement I and Statement II are correct

  2. B.

    Both Statement I and Statement II are incorrect

  3. C.

    Statement I is correct but Statement II is incorrect

  4. D.

    Statement I is incorrect but Statement II is correct

Show answer & explanation

Correct answer: D

CONCEPT

An inclusive arithmetic series from a to b has n = b − a + 1 terms and sum S = n(a + b)/2.

For a circle, C = 2πr, A = πr2, and d = 2r; proportionality is identified after common factors are simplified.

APPLICATION

  1. Count the integers inclusively: n = 630 − 110 + 1 = 521.

  2. Compute the sum: S = 521(110 + 630)/2 = 521 × 370 = 192,770. This is below 300,000, so Statement I is incorrect.

  3. Form the circle ratio: C/A = 2πr/(πr2) = 2/r.

  4. Use r = d/2: 2/(d/2) = 4/d. Thus the ratio varies inversely with diameter, so Statement II is correct.

CROSS-CHECK

  • The average of the endpoints is 370, and 370 × 521 = 192,770, confirming the series result.

  • If d doubles, 4/d halves, confirming inverse proportionality.

RESULT

Therefore, Statement I is incorrect but Statement II is correct.

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