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Finding the Fourth Proportional to 165.39, 228.20 and 103.20

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Solution

The fourth proportional to 165.39, 228.20 and 103.20 is: 142.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    165.39 : 228.20 = 103.20 : x
  2. Step 2: Convert to fraction form
    165.39/228.20 = 103.20/x
  3. Step 3: Cross multiply
    165.39x = 228.20 × 103.20
  4. Step 4: Simplify right side
    165.39x = 23,550.24
  5. Step 5: Solve for x
    x = 23,550.24/165.39
  6. Step 6: Final answer
    x = 142.39

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.