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Finding the Fourth Proportional to 71.71, 108.08 and 67.80

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Solution

The fourth proportional to 71.71, 108.08 and 67.80 is: 102.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.71 : 108.08 = 67.80 : x
  2. Step 2: Convert to fraction form
    71.71/108.08 = 67.80/x
  3. Step 3: Cross multiply
    71.71x = 108.08 × 67.80
  4. Step 4: Simplify right side
    71.71x = 7,327.82
  5. Step 5: Solve for x
    x = 7,327.82/71.71
  6. Step 6: Final answer
    x = 102.19

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.