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Finding the Fourth Proportional to 539.36, 809.78 and 429.74

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Solution

The fourth proportional to 539.36, 809.78 and 429.74 is: 645.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.36 : 809.78 = 429.74 : x
  2. Step 2: Convert to fraction form
    539.36/809.78 = 429.74/x
  3. Step 3: Cross multiply
    539.36x = 809.78 × 429.74
  4. Step 4: Simplify right side
    539.36x = 347,988.66
  5. Step 5: Solve for x
    x = 347,988.66/539.36
  6. Step 6: Final answer
    x = 645.19

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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.