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Finding the Fourth Proportional to 660.44, 988.61 and 428.83

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Solution

The fourth proportional to 660.44, 988.61 and 428.83 is: 641.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.44 : 988.61 = 428.83 : x
  2. Step 2: Convert to fraction form
    660.44/988.61 = 428.83/x
  3. Step 3: Cross multiply
    660.44x = 988.61 × 428.83
  4. Step 4: Simplify right side
    660.44x = 423,945.63
  5. Step 5: Solve for x
    x = 423,945.63/660.44
  6. Step 6: Final answer
    x = 641.91

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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.