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Finding the Fourth Proportional to 660.46, 990.55 and 425.49

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Solution

The fourth proportional to 660.46, 990.55 and 425.49 is: 638.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.46 : 990.55 = 425.49 : x
  2. Step 2: Convert to fraction form
    660.46/990.55 = 425.49/x
  3. Step 3: Cross multiply
    660.46x = 990.55 × 425.49
  4. Step 4: Simplify right side
    660.46x = 421,469.12
  5. Step 5: Solve for x
    x = 421,469.12/660.46
  6. Step 6: Final answer
    x = 638.14

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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.