Hard GCSE Maths: Scale decimals using given product

Source: savemyexams.com

TL;DR

• Hard exam question 2 tests related decimal multiplications using a given fact.
• Use 0.4 × 0.25 = 0.1 to find 0.04 × 0.025 and 0.004 × 0.0025, each worth 1 mark.
• Builds skill in scaling calculations without direct computation for GCSE higher tier.

The story at a glance

This page from Save My Exams hosts Edexcel GCSE Maths Higher exam questions on number operations, with hard-2 as a specific 2-mark problem on decimal multiplication. Students must apply the given equality 0.4 × 0.25 = 0.1 to two similar products. It appears now as part of ongoing revision resources for the 1MA1 syllabus.

Key points

• Question from Edexcel GCSE Maths Higher (1MA1), topic: number operations, difficulty: hard.
• Part (i) (1 mark): Find 0.04 × 0.025 using the fact.
• Part (ii) (1 mark): Find 0.004 × 0.0025 using the same fact.
• No diagrams or multiple-choice; pure calculation via pattern recognition.
• Full solutions behind login on site ("View answer Watch Solution").

Details and context

The question teaches "related calculations," a key higher-tier skill where students spot patterns in multiplications to avoid long direct work—like shifting decimals left twice each in both factors from the given.

For part (i): 0.04 = 0.4 / 10, 0.025 = 0.25 / 10, so product is 0.1 / 100 = 0.001.

For part (ii): Each factor divided by 10 again, so 0.1 / 10,000 = 0.00001.

This matches Edexcel's emphasis on efficient number handling in exams.

Why it matters

Mastering related calculations saves time in exams with tight limits. Students gain confidence handling small decimals without calculator errors. Watch for similar patterns in mocks or past papers like those on Save My Exams.

LANG: en

[[1]](https://www.savemyexams.com/gcse/maths/edexcel/22/higher/topic-questions/number/number-operations/exam-questions/#hard-2)