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Finding the Fourth Proportional to 687.37, 947.86 and 477.79

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Solution

The fourth proportional to 687.37, 947.86 and 477.79 is: 658.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.37 : 947.86 = 477.79 : x
  2. Step 2: Convert to fraction form
    687.37/947.86 = 477.79/x
  3. Step 3: Cross multiply
    687.37x = 947.86 × 477.79
  4. Step 4: Simplify right side
    687.37x = 452,878.03
  5. Step 5: Solve for x
    x = 452,878.03/687.37
  6. Step 6: Final answer
    x = 658.86

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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.