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Finding the Fourth Proportional to 108.30, 149.08 and 89.85

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Solution

The fourth proportional to 108.30, 149.08 and 89.85 is: 123.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.30 : 149.08 = 89.85 : x
  2. Step 2: Convert to fraction form
    108.30/149.08 = 89.85/x
  3. Step 3: Cross multiply
    108.30x = 149.08 × 89.85
  4. Step 4: Simplify right side
    108.30x = 13,394.84
  5. Step 5: Solve for x
    x = 13,394.84/108.30
  6. Step 6: Final answer
    x = 123.68

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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.