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Finding the Fourth Proportional to 61.03, 91.56 and 20.45

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Solution

The fourth proportional to 61.03, 91.56 and 20.45 is: 30.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.03 : 91.56 = 20.45 : x
  2. Step 2: Convert to fraction form
    61.03/91.56 = 20.45/x
  3. Step 3: Cross multiply
    61.03x = 91.56 × 20.45
  4. Step 4: Simplify right side
    61.03x = 1,872.59
  5. Step 5: Solve for x
    x = 1,872.59/61.03
  6. Step 6: Final answer
    x = 30.69

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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.