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Finding the Fourth Proportional to 53.87, 80.39 and 47.80

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Solution

The fourth proportional to 53.87, 80.39 and 47.80 is: 71.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    53.87 : 80.39 = 47.80 : x
  2. Step 2: Convert to fraction form
    53.87/80.39 = 47.80/x
  3. Step 3: Cross multiply
    53.87x = 80.39 × 47.80
  4. Step 4: Simplify right side
    53.87x = 3,842.64
  5. Step 5: Solve for x
    x = 3,842.64/53.87
  6. Step 6: Final answer
    x = 71.33

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.