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Finding the Fourth Proportional to 30.06, 45.09 and 20.31

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Solution

The fourth proportional to 30.06, 45.09 and 20.31 is: 30.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.06 : 45.09 = 20.31 : x
  2. Step 2: Convert to fraction form
    30.06/45.09 = 20.31/x
  3. Step 3: Cross multiply
    30.06x = 45.09 × 20.31
  4. Step 4: Simplify right side
    30.06x = 915.78
  5. Step 5: Solve for x
    x = 915.78/30.06
  6. Step 6: Final answer
    x = 30.47

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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.