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Finding the Fourth Proportional to 108.77, 149.81 and 81.09

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Solution

The fourth proportional to 108.77, 149.81 and 81.09 is: 111.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.77 : 149.81 = 81.09 : x
  2. Step 2: Convert to fraction form
    108.77/149.81 = 81.09/x
  3. Step 3: Cross multiply
    108.77x = 149.81 × 81.09
  4. Step 4: Simplify right side
    108.77x = 12,148.34
  5. Step 5: Solve for x
    x = 12,148.34/108.77
  6. Step 6: Final answer
    x = 111.69

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Find fourth proportional to 54.38, 74.90 and 40.55
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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.