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Finding the Fourth Proportional to 638.10, 957.48 and 272.79

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Solution

The fourth proportional to 638.10, 957.48 and 272.79 is: 409.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.10 : 957.48 = 272.79 : x
  2. Step 2: Convert to fraction form
    638.10/957.48 = 272.79/x
  3. Step 3: Cross multiply
    638.10x = 957.48 × 272.79
  4. Step 4: Simplify right side
    638.10x = 261,189.95
  5. Step 5: Solve for x
    x = 261,189.95/638.10
  6. Step 6: Final answer
    x = 409.32

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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.