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Finding the Fourth Proportional to 638.68, 957.12 and 406.84

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Solution

The fourth proportional to 638.68, 957.12 and 406.84 is: 609.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.68 : 957.12 = 406.84 : x
  2. Step 2: Convert to fraction form
    638.68/957.12 = 406.84/x
  3. Step 3: Cross multiply
    638.68x = 957.12 × 406.84
  4. Step 4: Simplify right side
    638.68x = 389,394.70
  5. Step 5: Solve for x
    x = 389,394.70/638.68
  6. Step 6: Final answer
    x = 609.69

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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.