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Finding the Fourth Proportional to 30.33, 42.07 and 27.90

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Solution

The fourth proportional to 30.33, 42.07 and 27.90 is: 38.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.33 : 42.07 = 27.90 : x
  2. Step 2: Convert to fraction form
    30.33/42.07 = 27.90/x
  3. Step 3: Cross multiply
    30.33x = 42.07 × 27.90
  4. Step 4: Simplify right side
    30.33x = 1,173.75
  5. Step 5: Solve for x
    x = 1,173.75/30.33
  6. Step 6: Final answer
    x = 38.70

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.