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Finding the Fourth Proportional to 71.55, 107.30 and 20.19

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Solution

The fourth proportional to 71.55, 107.30 and 20.19 is: 30.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.55 : 107.30 = 20.19 : x
  2. Step 2: Convert to fraction form
    71.55/107.30 = 20.19/x
  3. Step 3: Cross multiply
    71.55x = 107.30 × 20.19
  4. Step 4: Simplify right side
    71.55x = 2,166.04
  5. Step 5: Solve for x
    x = 2,166.04/71.55
  6. Step 6: Final answer
    x = 30.27

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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.