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Finding the Fourth Proportional to 520.80, 779.28 and 507.84

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Solution

The fourth proportional to 520.80, 779.28 and 507.84 is: 759.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.80 : 779.28 = 507.84 : x
  2. Step 2: Convert to fraction form
    520.80/779.28 = 507.84/x
  3. Step 3: Cross multiply
    520.80x = 779.28 × 507.84
  4. Step 4: Simplify right side
    520.80x = 395,749.56
  5. Step 5: Solve for x
    x = 395,749.56/520.80
  6. Step 6: Final answer
    x = 759.89

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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.