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Finding the Fourth Proportional to 108.42, 162.42 and 87.18

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Solution

The fourth proportional to 108.42, 162.42 and 87.18 is: 130.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.42 : 162.42 = 87.18 : x
  2. Step 2: Convert to fraction form
    108.42/162.42 = 87.18/x
  3. Step 3: Cross multiply
    108.42x = 162.42 × 87.18
  4. Step 4: Simplify right side
    108.42x = 14,159.78
  5. Step 5: Solve for x
    x = 14,159.78/108.42
  6. Step 6: Final answer
    x = 130.60

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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.