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Finding the Fourth Proportional to 643.48, 887.97 and 381.58

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Solution

The fourth proportional to 643.48, 887.97 and 381.58 is: 526.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.48 : 887.97 = 381.58 : x
  2. Step 2: Convert to fraction form
    643.48/887.97 = 381.58/x
  3. Step 3: Cross multiply
    643.48x = 887.97 × 381.58
  4. Step 4: Simplify right side
    643.48x = 338,831.59
  5. Step 5: Solve for x
    x = 338,831.59/643.48
  6. Step 6: Final answer
    x = 526.56

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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.