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Finding the Fourth Proportional to 686.81, 948.51 and 511.85

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Solution

The fourth proportional to 686.81, 948.51 and 511.85 is: 706.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.81 : 948.51 = 511.85 : x
  2. Step 2: Convert to fraction form
    686.81/948.51 = 511.85/x
  3. Step 3: Cross multiply
    686.81x = 948.51 × 511.85
  4. Step 4: Simplify right side
    686.81x = 485,497.21
  5. Step 5: Solve for x
    x = 485,497.21/686.81
  6. Step 6: Final answer
    x = 706.88

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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.