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Finding the Fourth Proportional to 664.88, 917.03 and 487.78

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Solution

The fourth proportional to 664.88, 917.03 and 487.78 is: 672.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.88 : 917.03 = 487.78 : x
  2. Step 2: Convert to fraction form
    664.88/917.03 = 487.78/x
  3. Step 3: Cross multiply
    664.88x = 917.03 × 487.78
  4. Step 4: Simplify right side
    664.88x = 447,307.82
  5. Step 5: Solve for x
    x = 447,307.82/664.88
  6. Step 6: Final answer
    x = 672.77

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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.