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Finding the Fourth Proportional to 53.45, 80.21 and 39.88

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Solution

The fourth proportional to 53.45, 80.21 and 39.88 is: 59.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    53.45 : 80.21 = 39.88 : x
  2. Step 2: Convert to fraction form
    53.45/80.21 = 39.88/x
  3. Step 3: Cross multiply
    53.45x = 80.21 × 39.88
  4. Step 4: Simplify right side
    53.45x = 3,198.37
  5. Step 5: Solve for x
    x = 3,198.37/53.45
  6. Step 6: Final answer
    x = 59.84

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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.