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Finding the Fourth Proportional to 84.39, 126.42 and 53.88

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Solution

The fourth proportional to 84.39, 126.42 and 53.88 is: 80.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.39 : 126.42 = 53.88 : x
  2. Step 2: Convert to fraction form
    84.39/126.42 = 53.88/x
  3. Step 3: Cross multiply
    84.39x = 126.42 × 53.88
  4. Step 4: Simplify right side
    84.39x = 6,811.51
  5. Step 5: Solve for x
    x = 6,811.51/84.39
  6. Step 6: Final answer
    x = 80.71

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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.