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Finding the Fourth Proportional to 643.08, 965.16 and 489.18

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Solution

The fourth proportional to 643.08, 965.16 and 489.18 is: 734.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.08 : 965.16 = 489.18 : x
  2. Step 2: Convert to fraction form
    643.08/965.16 = 489.18/x
  3. Step 3: Cross multiply
    643.08x = 965.16 × 489.18
  4. Step 4: Simplify right side
    643.08x = 472,136.97
  5. Step 5: Solve for x
    x = 472,136.97/643.08
  6. Step 6: Final answer
    x = 734.18

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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.