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Finding the Fourth Proportional to 108.23, 149.31 and 66.78

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Solution

The fourth proportional to 108.23, 149.31 and 66.78 is: 92.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.23 : 149.31 = 66.78 : x
  2. Step 2: Convert to fraction form
    108.23/149.31 = 66.78/x
  3. Step 3: Cross multiply
    108.23x = 149.31 × 66.78
  4. Step 4: Simplify right side
    108.23x = 9,970.92
  5. Step 5: Solve for x
    x = 9,970.92/108.23
  6. Step 6: Final answer
    x = 92.13

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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.