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Finding the Fourth Proportional to 108.12, 148.78 and 83.55

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Solution

The fourth proportional to 108.12, 148.78 and 83.55 is: 114.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.12 : 148.78 = 83.55 : x
  2. Step 2: Convert to fraction form
    108.12/148.78 = 83.55/x
  3. Step 3: Cross multiply
    108.12x = 148.78 × 83.55
  4. Step 4: Simplify right side
    108.12x = 12,430.57
  5. Step 5: Solve for x
    x = 12,430.57/108.12
  6. Step 6: Final answer
    x = 114.97

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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.