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Finding the Fourth Proportional to 657.72, 986.25 and 426.72

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Solution

The fourth proportional to 657.72, 986.25 and 426.72 is: 639.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.72 : 986.25 = 426.72 : x
  2. Step 2: Convert to fraction form
    657.72/986.25 = 426.72/x
  3. Step 3: Cross multiply
    657.72x = 986.25 × 426.72
  4. Step 4: Simplify right side
    657.72x = 420,852.60
  5. Step 5: Solve for x
    x = 420,852.60/657.72
  6. Step 6: Final answer
    x = 639.87

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.