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Finding the Fourth Proportional to 638.33, 881.06 and 389.81

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Solution

The fourth proportional to 638.33, 881.06 and 389.81 is: 538.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.33 : 881.06 = 389.81 : x
  2. Step 2: Convert to fraction form
    638.33/881.06 = 389.81/x
  3. Step 3: Cross multiply
    638.33x = 881.06 × 389.81
  4. Step 4: Simplify right side
    638.33x = 343,446.25
  5. Step 5: Solve for x
    x = 343,446.25/638.33
  6. Step 6: Final answer
    x = 538.04

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.