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Finding the Fourth Proportional to 20.95, 31.37 and 15.51

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Solution

The fourth proportional to 20.95, 31.37 and 15.51 is: 23.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    20.95 : 31.37 = 15.51 : x
  2. Step 2: Convert to fraction form
    20.95/31.37 = 15.51/x
  3. Step 3: Cross multiply
    20.95x = 31.37 × 15.51
  4. Step 4: Simplify right side
    20.95x = 486.47
  5. Step 5: Solve for x
    x = 486.47/20.95
  6. Step 6: Final answer
    x = 23.22

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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.