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Finding the Fourth Proportional to 638.23, 957.15 and 205.30

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Solution

The fourth proportional to 638.23, 957.15 and 205.30 is: 307.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.23 : 957.15 = 205.30 : x
  2. Step 2: Convert to fraction form
    638.23/957.15 = 205.30/x
  3. Step 3: Cross multiply
    638.23x = 957.15 × 205.30
  4. Step 4: Simplify right side
    638.23x = 196,502.90
  5. Step 5: Solve for x
    x = 196,502.90/638.23
  6. Step 6: Final answer
    x = 307.89

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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.