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Finding the Fourth Proportional to 522.88, 720.72 and 391.66

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Solution

The fourth proportional to 522.88, 720.72 and 391.66 is: 539.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    522.88 : 720.72 = 391.66 : x
  2. Step 2: Convert to fraction form
    522.88/720.72 = 391.66/x
  3. Step 3: Cross multiply
    522.88x = 720.72 × 391.66
  4. Step 4: Simplify right side
    522.88x = 282,275.39
  5. Step 5: Solve for x
    x = 282,275.39/522.88
  6. Step 6: Final answer
    x = 539.85

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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.