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Finding the Fourth Proportional to 643.14, 887.40 and 394.53

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Solution

The fourth proportional to 643.14, 887.40 and 394.53 is: 544.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.14 : 887.40 = 394.53 : x
  2. Step 2: Convert to fraction form
    643.14/887.40 = 394.53/x
  3. Step 3: Cross multiply
    643.14x = 887.40 × 394.53
  4. Step 4: Simplify right side
    643.14x = 350,105.92
  5. Step 5: Solve for x
    x = 350,105.92/643.14
  6. Step 6: Final answer
    x = 544.37

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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.