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Finding the Fourth Proportional to 513.75, 708.99 and 280.89

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Solution

The fourth proportional to 513.75, 708.99 and 280.89 is: 387.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.75 : 708.99 = 280.89 : x
  2. Step 2: Convert to fraction form
    513.75/708.99 = 280.89/x
  3. Step 3: Cross multiply
    513.75x = 708.99 × 280.89
  4. Step 4: Simplify right side
    513.75x = 199,148.20
  5. Step 5: Solve for x
    x = 199,148.20/513.75
  6. Step 6: Final answer
    x = 387.64

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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.