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Finding the Fourth Proportional to 522.39, 720.90 and 289.50

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Solution

The fourth proportional to 522.39, 720.90 and 289.50 is: 399.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    522.39 : 720.90 = 289.50 : x
  2. Step 2: Convert to fraction form
    522.39/720.90 = 289.50/x
  3. Step 3: Cross multiply
    522.39x = 720.90 × 289.50
  4. Step 4: Simplify right side
    522.39x = 208,700.55
  5. Step 5: Solve for x
    x = 208,700.55/522.39
  6. Step 6: Final answer
    x = 399.51

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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.