Unit 6 · Algebra

Sweetcorn Can Puzzle — Find the Three-Quarters-Full Weight

Lesson 24 of 24

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About this lesson

Two scenarios give you two equations: C + S/2 = 120 and C + S/4 = 65. Subtract to get S/4 = 55, so full sweetcorn = 220 g and the can = 10 g. Three-quarters full = 10 + 165 = 175 g.

Chapters

0:00Introduction
0:24The Question
1:05Aligning the given states symmetrically
1:33Calculating the weight of a single quarter unit
2:02Scaling up directly to the three-quarters target
2:34Exam strategy — eliminating the empty can diversion
3:23Confirming the final option

Question

When this can of sweetcorn is half full the sweetcorn and can together have a mass of 120 grams.

When the can of sweetcorn is one-quarter full the sweetcorn and can together have a mass of 65 g.

What is the mass of the can and sweetcorn together when the can is three-quarters full?

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