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Finding the Fourth Proportional to 30.21, 45.09 and 28.07

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Solution

The fourth proportional to 30.21, 45.09 and 28.07 is: 41.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.21 : 45.09 = 28.07 : x
  2. Step 2: Convert to fraction form
    30.21/45.09 = 28.07/x
  3. Step 3: Cross multiply
    30.21x = 45.09 × 28.07
  4. Step 4: Simplify right side
    30.21x = 1,265.68
  5. Step 5: Solve for x
    x = 1,265.68/30.21
  6. Step 6: Final answer
    x = 41.90

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.