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Finding the Fourth Proportional to 643.32, 887.92 and 381.32

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Solution

The fourth proportional to 643.32, 887.92 and 381.32 is: 526.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.32 : 887.92 = 381.32 : x
  2. Step 2: Convert to fraction form
    643.32/887.92 = 381.32/x
  3. Step 3: Cross multiply
    643.32x = 887.92 × 381.32
  4. Step 4: Simplify right side
    643.32x = 338,581.65
  5. Step 5: Solve for x
    x = 338,581.65/643.32
  6. Step 6: Final answer
    x = 526.30

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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.