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Finding the Fourth Proportional to 638.66, 956.58 and 621.44

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Solution

The fourth proportional to 638.66, 956.58 and 621.44 is: 930.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.66 : 956.58 = 621.44 : x
  2. Step 2: Convert to fraction form
    638.66/956.58 = 621.44/x
  3. Step 3: Cross multiply
    638.66x = 956.58 × 621.44
  4. Step 4: Simplify right side
    638.66x = 594,457.08
  5. Step 5: Solve for x
    x = 594,457.08/638.66
  6. Step 6: Final answer
    x = 930.79

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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.