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Finding the Fourth Proportional to 663.65, 915.87 and 383.90

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Solution

The fourth proportional to 663.65, 915.87 and 383.90 is: 529.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.65 : 915.87 = 383.90 : x
  2. Step 2: Convert to fraction form
    663.65/915.87 = 383.90/x
  3. Step 3: Cross multiply
    663.65x = 915.87 × 383.90
  4. Step 4: Simplify right side
    663.65x = 351,601.35
  5. Step 5: Solve for x
    x = 351,601.35/663.65
  6. Step 6: Final answer
    x = 529.80

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.