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Finding the Fourth Proportional to 69.15, 103.29 and 51.15

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Solution

The fourth proportional to 69.15, 103.29 and 51.15 is: 76.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    69.15 : 103.29 = 51.15 : x
  2. Step 2: Convert to fraction form
    69.15/103.29 = 51.15/x
  3. Step 3: Cross multiply
    69.15x = 103.29 × 51.15
  4. Step 4: Simplify right side
    69.15x = 5,282.64
  5. Step 5: Solve for x
    x = 5,282.64/69.15
  6. Step 6: Final answer
    x = 76.40

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.