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Finding the Fourth Proportional to 643.24, 887.69 and 377.84

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Solution

The fourth proportional to 643.24, 887.69 and 377.84 is: 521.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.24 : 887.69 = 377.84 : x
  2. Step 2: Convert to fraction form
    643.24/887.69 = 377.84/x
  3. Step 3: Cross multiply
    643.24x = 887.69 × 377.84
  4. Step 4: Simplify right side
    643.24x = 335,404.79
  5. Step 5: Solve for x
    x = 335,404.79/643.24
  6. Step 6: Final answer
    x = 521.43

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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.