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Finding the Fourth Proportional to 539.80, 809.91 and 215.39

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Solution

The fourth proportional to 539.80, 809.91 and 215.39 is: 323.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.80 : 809.91 = 215.39 : x
  2. Step 2: Convert to fraction form
    539.80/809.91 = 215.39/x
  3. Step 3: Cross multiply
    539.80x = 809.91 × 215.39
  4. Step 4: Simplify right side
    539.80x = 174,448.54
  5. Step 5: Solve for x
    x = 174,448.54/539.80
  6. Step 6: Final answer
    x = 323.17

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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.