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Finding the Fourth Proportional to 6.78, 10.15 and 4.09

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Solution

The fourth proportional to 6.78, 10.15 and 4.09 is: 6.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.78 : 10.15 = 4.09 : x
  2. Step 2: Convert to fraction form
    6.78/10.15 = 4.09/x
  3. Step 3: Cross multiply
    6.78x = 10.15 × 4.09
  4. Step 4: Simplify right side
    6.78x = 41.51
  5. Step 5: Solve for x
    x = 41.51/6.78
  6. Step 6: Final answer
    x = 6.12

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.