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Finding the Fourth Proportional to 71.75, 108.18 and 68

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Solution

The fourth proportional to 71.75, 108.18 and 68 is: 102.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.75 : 108.18 = 68 : x
  2. Step 2: Convert to fraction form
    71.75/108.18 = 68/x
  3. Step 3: Cross multiply
    71.75x = 108.18 × 68
  4. Step 4: Simplify right side
    71.75x = 7,356.24
  5. Step 5: Solve for x
    x = 7,356.24/71.75
  6. Step 6: Final answer
    x = 102.53

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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.