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Finding the Fourth Proportional to 359.80, 539.70 and 287.80

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Solution

The fourth proportional to 359.80, 539.70 and 287.80 is: 431.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    359.80 : 539.70 = 287.80 : x
  2. Step 2: Convert to fraction form
    359.80/539.70 = 287.80/x
  3. Step 3: Cross multiply
    359.80x = 539.70 × 287.80
  4. Step 4: Simplify right side
    359.80x = 155,325.66
  5. Step 5: Solve for x
    x = 155,325.66/359.80
  6. Step 6: Final answer
    x = 431.70

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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.