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Finding the Fourth Proportional to 165.70, 247.89 and 128.85

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Solution

The fourth proportional to 165.70, 247.89 and 128.85 is: 192.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    165.70 : 247.89 = 128.85 : x
  2. Step 2: Convert to fraction form
    165.70/247.89 = 128.85/x
  3. Step 3: Cross multiply
    165.70x = 247.89 × 128.85
  4. Step 4: Simplify right side
    165.70x = 31,941.07
  5. Step 5: Solve for x
    x = 31,941.07/165.70
  6. Step 6: Final answer
    x = 192.76

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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.