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Finding the Fourth Proportional to 78.98, 108.77 and 68.61

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Solution

The fourth proportional to 78.98, 108.77 and 68.61 is: 94.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.98 : 108.77 = 68.61 : x
  2. Step 2: Convert to fraction form
    78.98/108.77 = 68.61/x
  3. Step 3: Cross multiply
    78.98x = 108.77 × 68.61
  4. Step 4: Simplify right side
    78.98x = 7,462.37
  5. Step 5: Solve for x
    x = 7,462.37/78.98
  6. Step 6: Final answer
    x = 94.49

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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.