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Finding the Fourth Proportional to 45.80, 68.64 and 20.09

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Solution

The fourth proportional to 45.80, 68.64 and 20.09 is: 30.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.80 : 68.64 = 20.09 : x
  2. Step 2: Convert to fraction form
    45.80/68.64 = 20.09/x
  3. Step 3: Cross multiply
    45.80x = 68.64 × 20.09
  4. Step 4: Simplify right side
    45.80x = 1,378.80
  5. Step 5: Solve for x
    x = 1,378.80/45.80
  6. Step 6: Final answer
    x = 30.10

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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.