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Finding the Fourth Proportional to 61.09, 91.61 and 20.50

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Solution

The fourth proportional to 61.09, 91.61 and 20.50 is: 30.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.09 : 91.61 = 20.50 : x
  2. Step 2: Convert to fraction form
    61.09/91.61 = 20.50/x
  3. Step 3: Cross multiply
    61.09x = 91.61 × 20.50
  4. Step 4: Simplify right side
    61.09x = 1,877.56
  5. Step 5: Solve for x
    x = 1,877.56/61.09
  6. Step 6: Final answer
    x = 30.74

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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.