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Finding the Fourth Proportional to 531.21, 732.78 and 391.71

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Solution

The fourth proportional to 531.21, 732.78 and 391.71 is: 540.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    531.21 : 732.78 = 391.71 : x
  2. Step 2: Convert to fraction form
    531.21/732.78 = 391.71/x
  3. Step 3: Cross multiply
    531.21x = 732.78 × 391.71
  4. Step 4: Simplify right side
    531.21x = 287,037.25
  5. Step 5: Solve for x
    x = 287,037.25/531.21
  6. Step 6: Final answer
    x = 540.35

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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.