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Finding the Fourth Proportional to 513.26, 708.31 and 280.40

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Solution

The fourth proportional to 513.26, 708.31 and 280.40 is: 386.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.26 : 708.31 = 280.40 : x
  2. Step 2: Convert to fraction form
    513.26/708.31 = 280.40/x
  3. Step 3: Cross multiply
    513.26x = 708.31 × 280.40
  4. Step 4: Simplify right side
    513.26x = 198,610.12
  5. Step 5: Solve for x
    x = 198,610.12/513.26
  6. Step 6: Final answer
    x = 386.96

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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.