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Finding the Fourth Proportional to 520.08, 780.20 and 303.20

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Solution

The fourth proportional to 520.08, 780.20 and 303.20 is: 454.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.08 : 780.20 = 303.20 : x
  2. Step 2: Convert to fraction form
    520.08/780.20 = 303.20/x
  3. Step 3: Cross multiply
    520.08x = 780.20 × 303.20
  4. Step 4: Simplify right side
    520.08x = 236,556.64
  5. Step 5: Solve for x
    x = 236,556.64/520.08
  6. Step 6: Final answer
    x = 454.85

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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.