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Finding the Fourth Proportional to 205.70, 308.55 and 83.88

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Solution

The fourth proportional to 205.70, 308.55 and 83.88 is: 125.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.70 : 308.55 = 83.88 : x
  2. Step 2: Convert to fraction form
    205.70/308.55 = 83.88/x
  3. Step 3: Cross multiply
    205.70x = 308.55 × 83.88
  4. Step 4: Simplify right side
    205.70x = 25,881.17
  5. Step 5: Solve for x
    x = 25,881.17/205.70
  6. Step 6: Final answer
    x = 125.82

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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.