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Finding the Fourth Proportional to 71.39, 107.21 and 53.29

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Solution

The fourth proportional to 71.39, 107.21 and 53.29 is: 80.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.39 : 107.21 = 53.29 : x
  2. Step 2: Convert to fraction form
    71.39/107.21 = 53.29/x
  3. Step 3: Cross multiply
    71.39x = 107.21 × 53.29
  4. Step 4: Simplify right side
    71.39x = 5,712.95
  5. Step 5: Solve for x
    x = 5,712.95/71.39
  6. Step 6: Final answer
    x = 80.02

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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.