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Finding the Fourth Proportional to 539.80, 809.78 and 215.16

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Solution

The fourth proportional to 539.80, 809.78 and 215.16 is: 322.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.80 : 809.78 = 215.16 : x
  2. Step 2: Convert to fraction form
    539.80/809.78 = 215.16/x
  3. Step 3: Cross multiply
    539.80x = 809.78 × 215.16
  4. Step 4: Simplify right side
    539.80x = 174,232.26
  5. Step 5: Solve for x
    x = 174,232.26/539.80
  6. Step 6: Final answer
    x = 322.77

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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.