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Finding the Fourth Proportional to 323.90, 485.63 and 128.92

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Solution

The fourth proportional to 323.90, 485.63 and 128.92 is: 193.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    323.90 : 485.63 = 128.92 : x
  2. Step 2: Convert to fraction form
    323.90/485.63 = 128.92/x
  3. Step 3: Cross multiply
    323.90x = 485.63 × 128.92
  4. Step 4: Simplify right side
    323.90x = 62,607.42
  5. Step 5: Solve for x
    x = 62,607.42/323.90
  6. Step 6: Final answer
    x = 193.29

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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.