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Finding the Fourth Proportional to 643.34, 965.05 and 489.58

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Solution

The fourth proportional to 643.34, 965.05 and 489.58 is: 734.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.34 : 965.05 = 489.58 : x
  2. Step 2: Convert to fraction form
    643.34/965.05 = 489.58/x
  3. Step 3: Cross multiply
    643.34x = 965.05 × 489.58
  4. Step 4: Simplify right side
    643.34x = 472,465.54
  5. Step 5: Solve for x
    x = 472,465.54/643.34
  6. Step 6: Final answer
    x = 734.39

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.