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Finding the Fourth Proportional to 323.49, 485.42 and 128.51

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Solution

The fourth proportional to 323.49, 485.42 and 128.51 is: 192.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    323.49 : 485.42 = 128.51 : x
  2. Step 2: Convert to fraction form
    323.49/485.42 = 128.51/x
  3. Step 3: Cross multiply
    323.49x = 485.42 × 128.51
  4. Step 4: Simplify right side
    323.49x = 62,378.25
  5. Step 5: Solve for x
    x = 62,378.25/323.49
  6. Step 6: Final answer
    x = 192.83

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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.