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Finding the Fourth Proportional to 43.55, 65.29 and 20.71

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Solution

The fourth proportional to 43.55, 65.29 and 20.71 is: 31.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    43.55 : 65.29 = 20.71 : x
  2. Step 2: Convert to fraction form
    43.55/65.29 = 20.71/x
  3. Step 3: Cross multiply
    43.55x = 65.29 × 20.71
  4. Step 4: Simplify right side
    43.55x = 1,352.16
  5. Step 5: Solve for x
    x = 1,352.16/43.55
  6. Step 6: Final answer
    x = 31.05

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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.