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Finding the Fourth Proportional to 522.80, 721.36 and 289.88

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Solution

The fourth proportional to 522.80, 721.36 and 289.88 is: 399.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    522.80 : 721.36 = 289.88 : x
  2. Step 2: Convert to fraction form
    522.80/721.36 = 289.88/x
  3. Step 3: Cross multiply
    522.80x = 721.36 × 289.88
  4. Step 4: Simplify right side
    522.80x = 209,107.84
  5. Step 5: Solve for x
    x = 209,107.84/522.80
  6. Step 6: Final answer
    x = 399.98

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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.