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Finding the Fourth Proportional to 659.80, 987.30 and 443.80

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Solution

The fourth proportional to 659.80, 987.30 and 443.80 is: 664.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.80 : 987.30 = 443.80 : x
  2. Step 2: Convert to fraction form
    659.80/987.30 = 443.80/x
  3. Step 3: Cross multiply
    659.80x = 987.30 × 443.80
  4. Step 4: Simplify right side
    659.80x = 438,163.74
  5. Step 5: Solve for x
    x = 438,163.74/659.80
  6. Step 6: Final answer
    x = 664.09

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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.