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Finding the Fourth Proportional to 643.28, 888.06 and 487.76

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Solution

The fourth proportional to 643.28, 888.06 and 487.76 is: 673.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.28 : 888.06 = 487.76 : x
  2. Step 2: Convert to fraction form
    643.28/888.06 = 487.76/x
  3. Step 3: Cross multiply
    643.28x = 888.06 × 487.76
  4. Step 4: Simplify right side
    643.28x = 433,160.15
  5. Step 5: Solve for x
    x = 433,160.15/643.28
  6. Step 6: Final answer
    x = 673.36

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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.