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Finding the Fourth Proportional to 513.80, 709 and 289.73

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Solution

The fourth proportional to 513.80, 709 and 289.73 is: 399.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.80 : 709 = 289.73 : x
  2. Step 2: Convert to fraction form
    513.80/709 = 289.73/x
  3. Step 3: Cross multiply
    513.80x = 709 × 289.73
  4. Step 4: Simplify right side
    513.80x = 205,418.57
  5. Step 5: Solve for x
    x = 205,418.57/513.80
  6. Step 6: Final answer
    x = 399.80

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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.