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Finding the Fourth Proportional to 77.93, 107.63 and 69.21

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Solution

The fourth proportional to 77.93, 107.63 and 69.21 is: 95.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.93 : 107.63 = 69.21 : x
  2. Step 2: Convert to fraction form
    77.93/107.63 = 69.21/x
  3. Step 3: Cross multiply
    77.93x = 107.63 × 69.21
  4. Step 4: Simplify right side
    77.93x = 7,449.07
  5. Step 5: Solve for x
    x = 7,449.07/77.93
  6. Step 6: Final answer
    x = 95.59

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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.