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Finding the Fourth Proportional to 75.78, 105.08 and 72.95

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Solution

The fourth proportional to 75.78, 105.08 and 72.95 is: 101.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.78 : 105.08 = 72.95 : x
  2. Step 2: Convert to fraction form
    75.78/105.08 = 72.95/x
  3. Step 3: Cross multiply
    75.78x = 105.08 × 72.95
  4. Step 4: Simplify right side
    75.78x = 7,664.70
  5. Step 5: Solve for x
    x = 7,664.70/75.78
  6. Step 6: Final answer
    x = 101.14

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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.