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Finding the Fourth Proportional to 205.15, 307.70 and 68.19

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Solution

The fourth proportional to 205.15, 307.70 and 68.19 is: 102.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.15 : 307.70 = 68.19 : x
  2. Step 2: Convert to fraction form
    205.15/307.70 = 68.19/x
  3. Step 3: Cross multiply
    205.15x = 307.70 × 68.19
  4. Step 4: Simplify right side
    205.15x = 20,982.06
  5. Step 5: Solve for x
    x = 20,982.06/205.15
  6. Step 6: Final answer
    x = 102.28

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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.