Lesson eLearning

In the sequence 10, 20, 30, …, 200, what is the 15th number?

hard 2 marks Class 2 · Mathematics · Counting in Tens
Answer
150

The correct answer is 150 — Therefore the 15th number is 150.

Step-by-step solution

  1. Each term is 10 × n where n starts at 1.
  2. The 15th term corresponds to n = 15.
  3. Compute 10 × 15 = 150.
  4. Therefore the 15th number is 150.
Common mistake: Multiplying 15 by 10 incorrectly

Concept tested: Finding nth term in multiples of ten

Published · How this solution was prepared and checked

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