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Rates, SM-Bank 066

A farmers' market sells potatoes in four different sizes.

Size 1 kg 2 kg 3 kg 5 kg
Price $3.40 $6.10 $9.30 $15.75

What is the lowest price a customer can pay for 8 kg of potatoes?  (2 marks)

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\($24.40\)

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\(\text{Calculate the cost per kg for each size:}\)

\(1\text{kg}\) \(=$3.40\text{/kg}\)
\(2\text{kg}\) \(=\dfrac{6.10}{2} = $3.05\text{/kg}\)
\(3\text{kg}\) \(=\dfrac{9.30}{3} = $3.10\text{/kg}\)
\(4\text{kg}\) \(=\dfrac{15.75}{5} =$3.15\text{/kg}\)

 

\(\therefore\ 2\text{kg packet is the cheapest.}\)
 

\(\therefore\ \text{Cheapest price to buy 8 kg}\)

\(=4\times 6.10\)

\(=$24.40\)