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Finding the Fourth Proportional to 638.28, 957.20 and 205.32

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Solution

The fourth proportional to 638.28, 957.20 and 205.32 is: 307.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.28 : 957.20 = 205.32 : x
  2. Step 2: Convert to fraction form
    638.28/957.20 = 205.32/x
  3. Step 3: Cross multiply
    638.28x = 957.20 × 205.32
  4. Step 4: Simplify right side
    638.28x = 196,531.28
  5. Step 5: Solve for x
    x = 196,531.28/638.28
  6. Step 6: Final answer
    x = 307.91

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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.