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Finding the Fourth Proportional to 105.38, 145.42 and 66.58

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Solution

The fourth proportional to 105.38, 145.42 and 66.58 is: 91.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.38 : 145.42 = 66.58 : x
  2. Step 2: Convert to fraction form
    105.38/145.42 = 66.58/x
  3. Step 3: Cross multiply
    105.38x = 145.42 × 66.58
  4. Step 4: Simplify right side
    105.38x = 9,682.06
  5. Step 5: Solve for x
    x = 9,682.06/105.38
  6. Step 6: Final answer
    x = 91.88

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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.