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Finding the Fourth Proportional to 205.58, 307.97 and 128.18

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Solution

The fourth proportional to 205.58, 307.97 and 128.18 is: 192.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.58 : 307.97 = 128.18 : x
  2. Step 2: Convert to fraction form
    205.58/307.97 = 128.18/x
  3. Step 3: Cross multiply
    205.58x = 307.97 × 128.18
  4. Step 4: Simplify right side
    205.58x = 39,475.59
  5. Step 5: Solve for x
    x = 39,475.59/205.58
  6. Step 6: Final answer
    x = 192.02

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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.