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Finding the Fourth Proportional to 638.19, 957.31 and 221.73

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Solution

The fourth proportional to 638.19, 957.31 and 221.73 is: 332.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.19 : 957.31 = 221.73 : x
  2. Step 2: Convert to fraction form
    638.19/957.31 = 221.73/x
  3. Step 3: Cross multiply
    638.19x = 957.31 × 221.73
  4. Step 4: Simplify right side
    638.19x = 212,261.45
  5. Step 5: Solve for x
    x = 212,261.45/638.19
  6. Step 6: Final answer
    x = 332.60

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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.