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Finding the Fourth Proportional to 521.85, 781.34 and 305.05

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Solution

The fourth proportional to 521.85, 781.34 and 305.05 is: 456.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.85 : 781.34 = 305.05 : x
  2. Step 2: Convert to fraction form
    521.85/781.34 = 305.05/x
  3. Step 3: Cross multiply
    521.85x = 781.34 × 305.05
  4. Step 4: Simplify right side
    521.85x = 238,346.24
  5. Step 5: Solve for x
    x = 238,346.24/521.85
  6. Step 6: Final answer
    x = 456.73

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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.