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Finding the Fourth Proportional to 205.40, 308.04 and 77.16

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Solution

The fourth proportional to 205.40, 308.04 and 77.16 is: 115.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.40 : 308.04 = 77.16 : x
  2. Step 2: Convert to fraction form
    205.40/308.04 = 77.16/x
  3. Step 3: Cross multiply
    205.40x = 308.04 × 77.16
  4. Step 4: Simplify right side
    205.40x = 23,768.37
  5. Step 5: Solve for x
    x = 23,768.37/205.40
  6. Step 6: Final answer
    x = 115.72

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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.