Unit 1 · Patterns and Sequences

Balancing Challenge — Total Halving Time

Lesson 4 of 7

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About this lesson

Each child balances for half as long as the one before. Write out all five times first, then add carefully — convert to seconds to avoid decimal traps.

Chapters

0:00Introduction
0:21The Question
1:06Listing the Balancing Time for Each Child
1:38Visualising the Sum with a Geometric Bar Model
2:02Calculating the Total Duration
2:38Exam Strategy — Decimal vs. Time Conversion
3:14Confirming the Final Option

Question

Five children take it in turn to do a balancing challenge, with each child completing it once.

The first child balances for 12 minutes.

After that, each child balances for half as long as the previous child.

What is the total time the five children are balancing?

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