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Finding the Fourth Proportional to 686.40, 947.98 and 437.60

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Solution

The fourth proportional to 686.40, 947.98 and 437.60 is: 604.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.40 : 947.98 = 437.60 : x
  2. Step 2: Convert to fraction form
    686.40/947.98 = 437.60/x
  3. Step 3: Cross multiply
    686.40x = 947.98 × 437.60
  4. Step 4: Simplify right side
    686.40x = 414,836.05
  5. Step 5: Solve for x
    x = 414,836.05/686.40
  6. Step 6: Final answer
    x = 604.36

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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.