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Finding the Fourth Proportional to 45.86, 68.74 and 18.78

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Solution

The fourth proportional to 45.86, 68.74 and 18.78 is: 28.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.86 : 68.74 = 18.78 : x
  2. Step 2: Convert to fraction form
    45.86/68.74 = 18.78/x
  3. Step 3: Cross multiply
    45.86x = 68.74 × 18.78
  4. Step 4: Simplify right side
    45.86x = 1,290.94
  5. Step 5: Solve for x
    x = 1,290.94/45.86
  6. Step 6: Final answer
    x = 28.15

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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.