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Finding the Fourth Proportional to 643.38, 887.58 and 381.30

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Solution

The fourth proportional to 643.38, 887.58 and 381.30 is: 526.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.38 : 887.58 = 381.30 : x
  2. Step 2: Convert to fraction form
    643.38/887.58 = 381.30/x
  3. Step 3: Cross multiply
    643.38x = 887.58 × 381.30
  4. Step 4: Simplify right side
    643.38x = 338,434.25
  5. Step 5: Solve for x
    x = 338,434.25/643.38
  6. Step 6: Final answer
    x = 526.03

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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.