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Finding the Fourth Proportional to 47.89, 71.79 and 45.20

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Solution

The fourth proportional to 47.89, 71.79 and 45.20 is: 67.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.89 : 71.79 = 45.20 : x
  2. Step 2: Convert to fraction form
    47.89/71.79 = 45.20/x
  3. Step 3: Cross multiply
    47.89x = 71.79 × 45.20
  4. Step 4: Simplify right side
    47.89x = 3,245.09
  5. Step 5: Solve for x
    x = 3,245.09/47.89
  6. Step 6: Final answer
    x = 67.76

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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.