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Finding the Fourth Proportional to 78.31, 108.18 and 60.89

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Solution

The fourth proportional to 78.31, 108.18 and 60.89 is: 84.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.31 : 108.18 = 60.89 : x
  2. Step 2: Convert to fraction form
    78.31/108.18 = 60.89/x
  3. Step 3: Cross multiply
    78.31x = 108.18 × 60.89
  4. Step 4: Simplify right side
    78.31x = 6,587.08
  5. Step 5: Solve for x
    x = 6,587.08/78.31
  6. Step 6: Final answer
    x = 84.12

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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.