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Finding the Fourth Proportional to 521.07, 781.65 and 247.09

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Solution

The fourth proportional to 521.07, 781.65 and 247.09 is: 370.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.07 : 781.65 = 247.09 : x
  2. Step 2: Convert to fraction form
    521.07/781.65 = 247.09/x
  3. Step 3: Cross multiply
    521.07x = 781.65 × 247.09
  4. Step 4: Simplify right side
    521.07x = 193,137.90
  5. Step 5: Solve for x
    x = 193,137.90/521.07
  6. Step 6: Final answer
    x = 370.66

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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.