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Definitions:
  • R = liters per hour bottled
  • C = liters per dollar spent
    → So, C liters = $1
    → Or 1 liter = $1/C

Part 1: How many hours it will take to spend $20
We are given:
  • Machine bottles R liters/hour
  • It costs $1 for every C liters, so:
    • Cost per hour = (R liters/hour) × (1 dollar / C liters) = R/C dollars per hour
To find time (in hours) to spend $20, we use:
\(\text{Time} = \frac{\text{Total Cost}}{\text{Cost per Hour}} = \frac{20}{R/C} = \frac{20C}{R}\)
✔️ Correct value for hours to spend $20: 20C/R

Part 2: How many dollars will be spent in 3 minutes
3 minutes = 3/60 = 1/20 hours
We already found that Cost per hour = R/C dollars
Cost in 1/20 hour=\(\text{Cost in 1/20 hour} = \left(\frac{R}{C}\right) \times \left(\frac{1}{20}\right) = \frac{R}{20C}\)
✔️ Correct value for dollars spent in 3 minutes: R/20C

Final Answers:
  • Hours to Spend $20: 20C/R
  • Dollars Spent in 3 Minutes: R/20C
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