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Finding the Fourth Proportional to 205.20, 283.08 and 139.72

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Solution

The fourth proportional to 205.20, 283.08 and 139.72 is: 192.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.20 : 283.08 = 139.72 : x
  2. Step 2: Convert to fraction form
    205.20/283.08 = 139.72/x
  3. Step 3: Cross multiply
    205.20x = 283.08 × 139.72
  4. Step 4: Simplify right side
    205.20x = 39,551.94
  5. Step 5: Solve for x
    x = 39,551.94/205.20
  6. Step 6: Final answer
    x = 192.75

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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.