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Finding the Fourth Proportional to 236.85, 355.68 and 128.85

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Solution

The fourth proportional to 236.85, 355.68 and 128.85 is: 193.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    236.85 : 355.68 = 128.85 : x
  2. Step 2: Convert to fraction form
    236.85/355.68 = 128.85/x
  3. Step 3: Cross multiply
    236.85x = 355.68 × 128.85
  4. Step 4: Simplify right side
    236.85x = 45,829.37
  5. Step 5: Solve for x
    x = 45,829.37/236.85
  6. Step 6: Final answer
    x = 193.50

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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.