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Finding the Fourth Proportional to 323.82, 485.55 and 128.81

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Solution

The fourth proportional to 323.82, 485.55 and 128.81 is: 193.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    323.82 : 485.55 = 128.81 : x
  2. Step 2: Convert to fraction form
    323.82/485.55 = 128.81/x
  3. Step 3: Cross multiply
    323.82x = 485.55 × 128.81
  4. Step 4: Simplify right side
    323.82x = 62,541.27
  5. Step 5: Solve for x
    x = 62,541.27/323.82
  6. Step 6: Final answer
    x = 193.14

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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.