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Finding the Fourth Proportional to 638.52, 957.90 and 253.80

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Solution

The fourth proportional to 638.52, 957.90 and 253.80 is: 380.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.52 : 957.90 = 253.80 : x
  2. Step 2: Convert to fraction form
    638.52/957.90 = 253.80/x
  3. Step 3: Cross multiply
    638.52x = 957.90 × 253.80
  4. Step 4: Simplify right side
    638.52x = 243,115.02
  5. Step 5: Solve for x
    x = 243,115.02/638.52
  6. Step 6: Final answer
    x = 380.75

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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.