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Finding the Fourth Proportional to 539.80, 810.42 and 280

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Solution

The fourth proportional to 539.80, 810.42 and 280 is: 420.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.80 : 810.42 = 280 : x
  2. Step 2: Convert to fraction form
    539.80/810.42 = 280/x
  3. Step 3: Cross multiply
    539.80x = 810.42 × 280
  4. Step 4: Simplify right side
    539.80x = 226,917.60
  5. Step 5: Solve for x
    x = 226,917.60/539.80
  6. Step 6: Final answer
    x = 420.37

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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.