Unit 3 · Measurement and Data
500g or 2.5kg — Cheapest Way to Get 4 kg?
Lesson 7 of 12
About this lesson
Dog food comes in two sizes: 500 g for $1 and 2.5 kg for $4.50. Joe needs exactly 4 kg. What's the cheapest way to get there? This is a combination problem — you must first find all combinations of boxes that total exactly 4 kg, then compare costs. Options A to D are traps: they look cheaper but don't actually sum to 4 kg.
Chapters
Question
Woof dog food is sold in two different sizes.
A box containing 500 g costs $1.
A box containing 2½ kg costs $4.50.
Joe needs to buy exactly 4 kg of dog food.
What is the lowest total price he can pay?
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