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Finding the Fourth Proportional to 75.20, 103.79 and 69.05

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Solution

The fourth proportional to 75.20, 103.79 and 69.05 is: 95.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.20 : 103.79 = 69.05 : x
  2. Step 2: Convert to fraction form
    75.20/103.79 = 69.05/x
  3. Step 3: Cross multiply
    75.20x = 103.79 × 69.05
  4. Step 4: Simplify right side
    75.20x = 7,166.70
  5. Step 5: Solve for x
    x = 7,166.70/75.20
  6. Step 6: Final answer
    x = 95.30

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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.