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Finding the Fourth Proportional to 77.90, 108.01 and 73.80

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Solution

The fourth proportional to 77.90, 108.01 and 73.80 is: 102.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.90 : 108.01 = 73.80 : x
  2. Step 2: Convert to fraction form
    77.90/108.01 = 73.80/x
  3. Step 3: Cross multiply
    77.90x = 108.01 × 73.80
  4. Step 4: Simplify right side
    77.90x = 7,970.77
  5. Step 5: Solve for x
    x = 7,970.77/77.90
  6. Step 6: Final answer
    x = 102.33

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.