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Finding the Fourth Proportional to 513.59, 708.71 and 280.71

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Solution

The fourth proportional to 513.59, 708.71 and 280.71 is: 387.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.59 : 708.71 = 280.71 : x
  2. Step 2: Convert to fraction form
    513.59/708.71 = 280.71/x
  3. Step 3: Cross multiply
    513.59x = 708.71 × 280.71
  4. Step 4: Simplify right side
    513.59x = 198,940.58
  5. Step 5: Solve for x
    x = 198,940.58/513.59
  6. Step 6: Final answer
    x = 387.36

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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.