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Finding the Fourth Proportional to 57.08, 85.62 and 20.98

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Solution

The fourth proportional to 57.08, 85.62 and 20.98 is: 31.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    57.08 : 85.62 = 20.98 : x
  2. Step 2: Convert to fraction form
    57.08/85.62 = 20.98/x
  3. Step 3: Cross multiply
    57.08x = 85.62 × 20.98
  4. Step 4: Simplify right side
    57.08x = 1,796.31
  5. Step 5: Solve for x
    x = 1,796.31/57.08
  6. Step 6: Final answer
    x = 31.47

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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.