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Finding the Fourth Proportional to 638.09, 957.45 and 291.38

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Solution

The fourth proportional to 638.09, 957.45 and 291.38 is: 437.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.09 : 957.45 = 291.38 : x
  2. Step 2: Convert to fraction form
    638.09/957.45 = 291.38/x
  3. Step 3: Cross multiply
    638.09x = 957.45 × 291.38
  4. Step 4: Simplify right side
    638.09x = 278,976.99
  5. Step 5: Solve for x
    x = 278,976.99/638.09
  6. Step 6: Final answer
    x = 437.21

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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.