Question P6 An average is a total
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A shop recorded sales of $420, $380, $510, $490, and $450 over five days. What is the average daily sale? On the sixth day, the average sales over all six days was $450. What were the sales on the sixth day?
Answer
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Turn the average back into a total before doing anything with it.
In this one. A new value only moves an average if it differs from it — the average was already $450 and stayed $450, so the sixth day must be $450 itself.
The word 'average' appears alongside a group being split into two parts, or two separate journeys or trips being combined into one overall figure.
Children average two averages directly, such as averaging two speeds or two group averages, without weighting by how many, or how long, each part actually covers.
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