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Finding the Fourth Proportional to 518.10, 776.84 and 209.79

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Solution

The fourth proportional to 518.10, 776.84 and 209.79 is: 314.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.10 : 776.84 = 209.79 : x
  2. Step 2: Convert to fraction form
    518.10/776.84 = 209.79/x
  3. Step 3: Cross multiply
    518.10x = 776.84 × 209.79
  4. Step 4: Simplify right side
    518.10x = 162,972.21
  5. Step 5: Solve for x
    x = 162,972.21/518.10
  6. Step 6: Final answer
    x = 314.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.