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Finding the Fourth Proportional to 520.85, 780.64 and 303.98

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Solution

The fourth proportional to 520.85, 780.64 and 303.98 is: 455.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.85 : 780.64 = 303.98 : x
  2. Step 2: Convert to fraction form
    520.85/780.64 = 303.98/x
  3. Step 3: Cross multiply
    520.85x = 780.64 × 303.98
  4. Step 4: Simplify right side
    520.85x = 237,294.28
  5. Step 5: Solve for x
    x = 237,294.28/520.85
  6. Step 6: Final answer
    x = 455.59

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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.