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Finding the Fourth Proportional to 686.70, 947.64 and 376.20

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Solution

The fourth proportional to 686.70, 947.64 and 376.20 is: 519.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.70 : 947.64 = 376.20 : x
  2. Step 2: Convert to fraction form
    686.70/947.64 = 376.20/x
  3. Step 3: Cross multiply
    686.70x = 947.64 × 376.20
  4. Step 4: Simplify right side
    686.70x = 356,502.17
  5. Step 5: Solve for x
    x = 356,502.17/686.70
  6. Step 6: Final answer
    x = 519.15

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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.