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Finding the Fourth Proportional to 30.20, 45.29 and 9.91

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Solution

The fourth proportional to 30.20, 45.29 and 9.91 is: 14.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.20 : 45.29 = 9.91 : x
  2. Step 2: Convert to fraction form
    30.20/45.29 = 9.91/x
  3. Step 3: Cross multiply
    30.20x = 45.29 × 9.91
  4. Step 4: Simplify right side
    30.20x = 448.60
  5. Step 5: Solve for x
    x = 448.60/30.20
  6. Step 6: Final answer
    x = 14.86

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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.