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Finding the Fourth Proportional to 642.09, 884.32 and 553.55

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Solution

The fourth proportional to 642.09, 884.32 and 553.55 is: 762.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.09 : 884.32 = 553.55 : x
  2. Step 2: Convert to fraction form
    642.09/884.32 = 553.55/x
  3. Step 3: Cross multiply
    642.09x = 884.32 × 553.55
  4. Step 4: Simplify right side
    642.09x = 489,509.53
  5. Step 5: Solve for x
    x = 489,509.53/642.09
  6. Step 6: Final answer
    x = 762.37

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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.