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Finding the Fourth Proportional to 686.54, 947.33 and 387.77

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Solution

The fourth proportional to 686.54, 947.33 and 387.77 is: 535.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.54 : 947.33 = 387.77 : x
  2. Step 2: Convert to fraction form
    686.54/947.33 = 387.77/x
  3. Step 3: Cross multiply
    686.54x = 947.33 × 387.77
  4. Step 4: Simplify right side
    686.54x = 367,344.22
  5. Step 5: Solve for x
    x = 367,344.22/686.54
  6. Step 6: Final answer
    x = 535.07

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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.