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Finding the Fourth Proportional to 513.19, 708.21 and 280.31

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Solution

The fourth proportional to 513.19, 708.21 and 280.31 is: 386.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.19 : 708.21 = 280.31 : x
  2. Step 2: Convert to fraction form
    513.19/708.21 = 280.31/x
  3. Step 3: Cross multiply
    513.19x = 708.21 × 280.31
  4. Step 4: Simplify right side
    513.19x = 198,520.12
  5. Step 5: Solve for x
    x = 198,520.12/513.19
  6. Step 6: Final answer
    x = 386.84

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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.