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Finding the Fourth Proportional to 311.59, 428.91 and 300.25

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Solution

The fourth proportional to 311.59, 428.91 and 300.25 is: 413.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.59 : 428.91 = 300.25 : x
  2. Step 2: Convert to fraction form
    311.59/428.91 = 300.25/x
  3. Step 3: Cross multiply
    311.59x = 428.91 × 300.25
  4. Step 4: Simplify right side
    311.59x = 128,778.08
  5. Step 5: Solve for x
    x = 128,778.08/311.59
  6. Step 6: Final answer
    x = 413.30

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.