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Finding the Fourth Proportional to 70.88, 97.82 and 39.79

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Solution

The fourth proportional to 70.88, 97.82 and 39.79 is: 54.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.88 : 97.82 = 39.79 : x
  2. Step 2: Convert to fraction form
    70.88/97.82 = 39.79/x
  3. Step 3: Cross multiply
    70.88x = 97.82 × 39.79
  4. Step 4: Simplify right side
    70.88x = 3,892.26
  5. Step 5: Solve for x
    x = 3,892.26/70.88
  6. Step 6: Final answer
    x = 54.91

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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.