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Finding the Fourth Proportional to 45.85, 68.69 and 20.12

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Solution

The fourth proportional to 45.85, 68.69 and 20.12 is: 30.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.85 : 68.69 = 20.12 : x
  2. Step 2: Convert to fraction form
    45.85/68.69 = 20.12/x
  3. Step 3: Cross multiply
    45.85x = 68.69 × 20.12
  4. Step 4: Simplify right side
    45.85x = 1,382.19
  5. Step 5: Solve for x
    x = 1,382.19/45.85
  6. Step 6: Final answer
    x = 30.15

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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.