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Finding the Fourth Proportional to 45.78, 68.67 and 13.72

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Solution

The fourth proportional to 45.78, 68.67 and 13.72 is: 20.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.78 : 68.67 = 13.72 : x
  2. Step 2: Convert to fraction form
    45.78/68.67 = 13.72/x
  3. Step 3: Cross multiply
    45.78x = 68.67 × 13.72
  4. Step 4: Simplify right side
    45.78x = 942.19
  5. Step 5: Solve for x
    x = 942.19/45.78
  6. Step 6: Final answer
    x = 20.58

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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.