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Finding the Fourth Proportional to 638.32, 957.40 and 199.55

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Solution

The fourth proportional to 638.32, 957.40 and 199.55 is: 299.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.32 : 957.40 = 199.55 : x
  2. Step 2: Convert to fraction form
    638.32/957.40 = 199.55/x
  3. Step 3: Cross multiply
    638.32x = 957.40 × 199.55
  4. Step 4: Simplify right side
    638.32x = 191,049.17
  5. Step 5: Solve for x
    x = 191,049.17/638.32
  6. Step 6: Final answer
    x = 299.30

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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.