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Finding the Fourth Proportional to 643, 887.36 and 381.24

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Solution

The fourth proportional to 643, 887.36 and 381.24 is: 526.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    643 : 887.36 = 381.24 : x
  2. Step 2: Convert to fraction form
    643/887.36 = 381.24/x
  3. Step 3: Cross multiply
    643x = 887.36 × 381.24
  4. Step 4: Simplify right side
    643x = 338,297.13
  5. Step 5: Solve for x
    x = 338,297.13/643
  6. Step 6: Final answer
    x = 526.12

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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.