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Finding the Fourth Proportional to 78.77, 107.98 and 77.36

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Solution

The fourth proportional to 78.77, 107.98 and 77.36 is: 106.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.77 : 107.98 = 77.36 : x
  2. Step 2: Convert to fraction form
    78.77/107.98 = 77.36/x
  3. Step 3: Cross multiply
    78.77x = 107.98 × 77.36
  4. Step 4: Simplify right side
    78.77x = 8,353.03
  5. Step 5: Solve for x
    x = 8,353.03/78.77
  6. Step 6: Final answer
    x = 106.04

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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.