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Finding the Fourth Proportional to 659.39, 989.42 and 440.13

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Solution

The fourth proportional to 659.39, 989.42 and 440.13 is: 660.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.39 : 989.42 = 440.13 : x
  2. Step 2: Convert to fraction form
    659.39/989.42 = 440.13/x
  3. Step 3: Cross multiply
    659.39x = 989.42 × 440.13
  4. Step 4: Simplify right side
    659.39x = 435,474.93
  5. Step 5: Solve for x
    x = 435,474.93/659.39
  6. Step 6: Final answer
    x = 660.42

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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.