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Finding the Fourth Proportional to 71.20, 97.70 and 68.64

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Solution

The fourth proportional to 71.20, 97.70 and 68.64 is: 94.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.20 : 97.70 = 68.64 : x
  2. Step 2: Convert to fraction form
    71.20/97.70 = 68.64/x
  3. Step 3: Cross multiply
    71.20x = 97.70 × 68.64
  4. Step 4: Simplify right side
    71.20x = 6,706.13
  5. Step 5: Solve for x
    x = 6,706.13/71.20
  6. Step 6: Final answer
    x = 94.19

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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.