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Finding the Fourth Proportional to 663.65, 993.60 and 431.95

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Solution

The fourth proportional to 663.65, 993.60 and 431.95 is: 646.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.65 : 993.60 = 431.95 : x
  2. Step 2: Convert to fraction form
    663.65/993.60 = 431.95/x
  3. Step 3: Cross multiply
    663.65x = 993.60 × 431.95
  4. Step 4: Simplify right side
    663.65x = 429,183.04
  5. Step 5: Solve for x
    x = 429,183.04/663.65
  6. Step 6: Final answer
    x = 646.71

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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.