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Finding the Fourth Proportional to 686.28, 947.40 and 519.18

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Solution

The fourth proportional to 686.28, 947.40 and 519.18 is: 716.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.28 : 947.40 = 519.18 : x
  2. Step 2: Convert to fraction form
    686.28/947.40 = 519.18/x
  3. Step 3: Cross multiply
    686.28x = 947.40 × 519.18
  4. Step 4: Simplify right side
    686.28x = 491,871.13
  5. Step 5: Solve for x
    x = 491,871.13/686.28
  6. Step 6: Final answer
    x = 716.72

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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.