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Finding the Fourth Proportional to 78.60, 108.49 and 47.54

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Solution

The fourth proportional to 78.60, 108.49 and 47.54 is: 65.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.60 : 108.49 = 47.54 : x
  2. Step 2: Convert to fraction form
    78.60/108.49 = 47.54/x
  3. Step 3: Cross multiply
    78.60x = 108.49 × 47.54
  4. Step 4: Simplify right side
    78.60x = 5,157.25
  5. Step 5: Solve for x
    x = 5,157.25/78.60
  6. Step 6: Final answer
    x = 65.62

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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.