relationships between quantities - A movie theater sells popcorn in bags of different sizes. The table shows the volume of popcorn and the price of the bag.

Sangeetha Pulapaka (last edited 1 year ago) (Expert, Educator @Qalaxia)

A volume of 10 ounces of popcorn was $6 and a volume of 20 ounces cost $8

So, for every 10 ounces increase there is an increase of $2.

If there is a 5 ounce increase there is an increase of \frac{5 \cdot 2}{10} = 1 dollar.

35 ounces is a 10 ounce + 5 ounce increase so it cost $2 + $1 = $3, extra so $8 + $3 = $11.

Since extra 10 ounces cost $2,

3 ounces cost \frac{3\cdot 2}{10} =0.6 dollars.

48 ounces = 45 ounces + 3 ounces = $13 + $ 0.6 = $13.6

60 ounces is 58 ounces + 2 ounces

58 ounces is a 10 ounce increase over 48 so it costs $13.6+ $2 = $15.6.

We know that 10 ounces cost $2 extra

2 ounces will cost \frac{2 \cdot 2}{10} = \frac{4}{10} = 0.4 dollars extra

60 ounces = 58 ounces + 2 ounces = $15.6 + $0.4 = $16.

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