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Finding the Fourth Proportional to 20.15, 30.12 and 15.60

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Solution

The fourth proportional to 20.15, 30.12 and 15.60 is: 23.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.15 : 30.12 = 15.60 : x
  2. Step 2: Convert to fraction form
    20.15/30.12 = 15.60/x
  3. Step 3: Cross multiply
    20.15x = 30.12 × 15.60
  4. Step 4: Simplify right side
    20.15x = 469.82
  5. Step 5: Solve for x
    x = 469.82/20.15
  6. Step 6: Final answer
    x = 23.31

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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.