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Finding the Fourth Proportional to 66.77, 91.33 and 65.71

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Solution

The fourth proportional to 66.77, 91.33 and 65.71 is: 89.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.77 : 91.33 = 65.71 : x
  2. Step 2: Convert to fraction form
    66.77/91.33 = 65.71/x
  3. Step 3: Cross multiply
    66.77x = 91.33 × 65.71
  4. Step 4: Simplify right side
    66.77x = 6,001.29
  5. Step 5: Solve for x
    x = 6,001.29/66.77
  6. Step 6: Final answer
    x = 89.88

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.