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Finding the Fourth Proportional to 28.20, 42.27 and 15.35

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Solution

The fourth proportional to 28.20, 42.27 and 15.35 is: 23.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.20 : 42.27 = 15.35 : x
  2. Step 2: Convert to fraction form
    28.20/42.27 = 15.35/x
  3. Step 3: Cross multiply
    28.20x = 42.27 × 15.35
  4. Step 4: Simplify right side
    28.20x = 648.63
  5. Step 5: Solve for x
    x = 648.63/28.20
  6. Step 6: Final answer
    x = 23.00

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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.