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Finding the Fourth Proportional to 657.72, 985.59 and 520.20

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Solution

The fourth proportional to 657.72, 985.59 and 520.20 is: 779.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.72 : 985.59 = 520.20 : x
  2. Step 2: Convert to fraction form
    657.72/985.59 = 520.20/x
  3. Step 3: Cross multiply
    657.72x = 985.59 × 520.20
  4. Step 4: Simplify right side
    657.72x = 512,703.92
  5. Step 5: Solve for x
    x = 512,703.92/657.72
  6. Step 6: Final answer
    x = 779.52

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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.