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Finding the Fourth Proportional to 638.34, 957.07 and 221.77

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Solution

The fourth proportional to 638.34, 957.07 and 221.77 is: 332.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.34 : 957.07 = 221.77 : x
  2. Step 2: Convert to fraction form
    638.34/957.07 = 221.77/x
  3. Step 3: Cross multiply
    638.34x = 957.07 × 221.77
  4. Step 4: Simplify right side
    638.34x = 212,248.31
  5. Step 5: Solve for x
    x = 212,248.31/638.34
  6. Step 6: Final answer
    x = 332.50

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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.