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Finding the Fourth Proportional to 108.39, 162.59 and 87.15

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Solution

The fourth proportional to 108.39, 162.59 and 87.15 is: 130.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.39 : 162.59 = 87.15 : x
  2. Step 2: Convert to fraction form
    108.39/162.59 = 87.15/x
  3. Step 3: Cross multiply
    108.39x = 162.59 × 87.15
  4. Step 4: Simplify right side
    108.39x = 14,169.28
  5. Step 5: Solve for x
    x = 14,169.28/108.39
  6. Step 6: Final answer
    x = 130.73

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.