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Finding the Fourth Proportional to 108.20, 148.91 and 87.03

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Solution

The fourth proportional to 108.20, 148.91 and 87.03 is: 119.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.20 : 148.91 = 87.03 : x
  2. Step 2: Convert to fraction form
    108.20/148.91 = 87.03/x
  3. Step 3: Cross multiply
    108.20x = 148.91 × 87.03
  4. Step 4: Simplify right side
    108.20x = 12,959.20
  5. Step 5: Solve for x
    x = 12,959.20/108.20
  6. Step 6: Final answer
    x = 119.77

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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.