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Finding the Fourth Proportional to 520.80, 780.66 and 338.30

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Solution

The fourth proportional to 520.80, 780.66 and 338.30 is: 507.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.80 : 780.66 = 338.30 : x
  2. Step 2: Convert to fraction form
    520.80/780.66 = 338.30/x
  3. Step 3: Cross multiply
    520.80x = 780.66 × 338.30
  4. Step 4: Simplify right side
    520.80x = 264,097.28
  5. Step 5: Solve for x
    x = 264,097.28/520.80
  6. Step 6: Final answer
    x = 507.10

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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.