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Finding the Fourth Proportional to 521.07, 781.07 and 290.07

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Solution

The fourth proportional to 521.07, 781.07 and 290.07 is: 434.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.07 : 781.07 = 290.07 : x
  2. Step 2: Convert to fraction form
    521.07/781.07 = 290.07/x
  3. Step 3: Cross multiply
    521.07x = 781.07 × 290.07
  4. Step 4: Simplify right side
    521.07x = 226,563.52
  5. Step 5: Solve for x
    x = 226,563.52/521.07
  6. Step 6: Final answer
    x = 434.80

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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.