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Finding the Fourth Proportional to 540.80, 810.55 and 309.85

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Solution

The fourth proportional to 540.80, 810.55 and 309.85 is: 464.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.80 : 810.55 = 309.85 : x
  2. Step 2: Convert to fraction form
    540.80/810.55 = 309.85/x
  3. Step 3: Cross multiply
    540.80x = 810.55 × 309.85
  4. Step 4: Simplify right side
    540.80x = 251,148.92
  5. Step 5: Solve for x
    x = 251,148.92/540.80
  6. Step 6: Final answer
    x = 464.40

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.