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Finding the Fourth Proportional to 520.47, 780.70 and 305.42

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Solution

The fourth proportional to 520.47, 780.70 and 305.42 is: 458.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.47 : 780.70 = 305.42 : x
  2. Step 2: Convert to fraction form
    520.47/780.70 = 305.42/x
  3. Step 3: Cross multiply
    520.47x = 780.70 × 305.42
  4. Step 4: Simplify right side
    520.47x = 238,436.73
  5. Step 5: Solve for x
    x = 238,436.73/520.47
  6. Step 6: Final answer
    x = 458.12

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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.