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Finding the Fourth Proportional to 30.31, 45.55 and 20.19

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Solution

The fourth proportional to 30.31, 45.55 and 20.19 is: 30.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.31 : 45.55 = 20.19 : x
  2. Step 2: Convert to fraction form
    30.31/45.55 = 20.19/x
  3. Step 3: Cross multiply
    30.31x = 45.55 × 20.19
  4. Step 4: Simplify right side
    30.31x = 919.65
  5. Step 5: Solve for x
    x = 919.65/30.31
  6. Step 6: Final answer
    x = 30.34

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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.