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Finding the Fourth Proportional to 522.60, 721.18 and 289.72

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Solution

The fourth proportional to 522.60, 721.18 and 289.72 is: 399.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    522.60 : 721.18 = 289.72 : x
  2. Step 2: Convert to fraction form
    522.60/721.18 = 289.72/x
  3. Step 3: Cross multiply
    522.60x = 721.18 × 289.72
  4. Step 4: Simplify right side
    522.60x = 208,940.27
  5. Step 5: Solve for x
    x = 208,940.27/522.60
  6. Step 6: Final answer
    x = 399.81

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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.