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Finding the Fourth Proportional to 540.75, 811.17 and 420.87

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Solution

The fourth proportional to 540.75, 811.17 and 420.87 is: 631.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    540.75 : 811.17 = 420.87 : x
  2. Step 2: Convert to fraction form
    540.75/811.17 = 420.87/x
  3. Step 3: Cross multiply
    540.75x = 811.17 × 420.87
  4. Step 4: Simplify right side
    540.75x = 341,397.12
  5. Step 5: Solve for x
    x = 341,397.12/540.75
  6. Step 6: Final answer
    x = 631.34

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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.