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Finding the Fourth Proportional to 77.64, 107.10 and 69.81

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Solution

The fourth proportional to 77.64, 107.10 and 69.81 is: 96.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.64 : 107.10 = 69.81 : x
  2. Step 2: Convert to fraction form
    77.64/107.10 = 69.81/x
  3. Step 3: Cross multiply
    77.64x = 107.10 × 69.81
  4. Step 4: Simplify right side
    77.64x = 7,476.65
  5. Step 5: Solve for x
    x = 7,476.65/77.64
  6. Step 6: Final answer
    x = 96.30

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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.