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Finding the Fourth Proportional to 103.20, 142.42 and 66.34

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Solution

The fourth proportional to 103.20, 142.42 and 66.34 is: 91.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.20 : 142.42 = 66.34 : x
  2. Step 2: Convert to fraction form
    103.20/142.42 = 66.34/x
  3. Step 3: Cross multiply
    103.20x = 142.42 × 66.34
  4. Step 4: Simplify right side
    103.20x = 9,448.14
  5. Step 5: Solve for x
    x = 9,448.14/103.20
  6. Step 6: Final answer
    x = 91.55

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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.