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Finding the Fourth Proportional to 101.09, 139.47 and 66.12

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Solution

The fourth proportional to 101.09, 139.47 and 66.12 is: 91.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.09 : 139.47 = 66.12 : x
  2. Step 2: Convert to fraction form
    101.09/139.47 = 66.12/x
  3. Step 3: Cross multiply
    101.09x = 139.47 × 66.12
  4. Step 4: Simplify right side
    101.09x = 9,221.76
  5. Step 5: Solve for x
    x = 9,221.76/101.09
  6. Step 6: Final answer
    x = 91.23

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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.