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Finding the Fourth Proportional to 70.87, 97.78 and 49.89

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Solution

The fourth proportional to 70.87, 97.78 and 49.89 is: 68.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.87 : 97.78 = 49.89 : x
  2. Step 2: Convert to fraction form
    70.87/97.78 = 49.89/x
  3. Step 3: Cross multiply
    70.87x = 97.78 × 49.89
  4. Step 4: Simplify right side
    70.87x = 4,878.24
  5. Step 5: Solve for x
    x = 4,878.24/70.87
  6. Step 6: Final answer
    x = 68.83

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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.