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Finding the Fourth Proportional to 539.80, 780.55 and 539.80

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Solution

The fourth proportional to 539.80, 780.55 and 539.80 is: 780.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.80 : 780.55 = 539.80 : x
  2. Step 2: Convert to fraction form
    539.80/780.55 = 539.80/x
  3. Step 3: Cross multiply
    539.80x = 780.55 × 539.80
  4. Step 4: Simplify right side
    539.80x = 421,340.89
  5. Step 5: Solve for x
    x = 421,340.89/539.80
  6. Step 6: Final answer
    x = 780.55

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Why These Related Problems?

These problems maintain the same ratio (1.45) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.