The first term of an arithmetic sequence is and the common difference is . Find the sum of the first 11 terms.

Answer and explanation

Correct answer: C. 451

  1. Step 1: Find the last term: .
  2. Step 2: .
Answer
451.
Why not the others: 76: that is the last term, not the sum. 902: the factor is missing.

Practise more Number and Algebra.

Free questions with an explanation for every one, and full timed HKDSE (Hong Kong) mock tests.