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Finding the Fourth Proportional to 686.28, 947.04 and 375.78

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Solution

The fourth proportional to 686.28, 947.04 and 375.78 is: 518.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.28 : 947.04 = 375.78 : x
  2. Step 2: Convert to fraction form
    686.28/947.04 = 375.78/x
  3. Step 3: Cross multiply
    686.28x = 947.04 × 375.78
  4. Step 4: Simplify right side
    686.28x = 355,878.69
  5. Step 5: Solve for x
    x = 355,878.69/686.28
  6. Step 6: Final answer
    x = 518.56

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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.