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Finding the Fourth Proportional to 66.56, 91.83 and 38.91

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Solution

The fourth proportional to 66.56, 91.83 and 38.91 is: 53.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.56 : 91.83 = 38.91 : x
  2. Step 2: Convert to fraction form
    66.56/91.83 = 38.91/x
  3. Step 3: Cross multiply
    66.56x = 91.83 × 38.91
  4. Step 4: Simplify right side
    66.56x = 3,573.01
  5. Step 5: Solve for x
    x = 3,573.01/66.56
  6. Step 6: Final answer
    x = 53.69

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.