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Finding the Fourth Proportional to 43.70, 65.56 and 20.90

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Solution

The fourth proportional to 43.70, 65.56 and 20.90 is: 31.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    43.70 : 65.56 = 20.90 : x
  2. Step 2: Convert to fraction form
    43.70/65.56 = 20.90/x
  3. Step 3: Cross multiply
    43.70x = 65.56 × 20.90
  4. Step 4: Simplify right side
    43.70x = 1,370.20
  5. Step 5: Solve for x
    x = 1,370.20/43.70
  6. Step 6: Final answer
    x = 31.35

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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.