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Finding the Fourth Proportional to 323.74, 485.28 and 128.88

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Solution

The fourth proportional to 323.74, 485.28 and 128.88 is: 193.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    323.74 : 485.28 = 128.88 : x
  2. Step 2: Convert to fraction form
    323.74/485.28 = 128.88/x
  3. Step 3: Cross multiply
    323.74x = 485.28 × 128.88
  4. Step 4: Simplify right side
    323.74x = 62,541.75
  5. Step 5: Solve for x
    x = 62,541.75/323.74
  6. Step 6: Final answer
    x = 193.19

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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.