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Finding the Fourth Proportional to 13.08, 19.74 and 12.90

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Solution

The fourth proportional to 13.08, 19.74 and 12.90 is: 19.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.08 : 19.74 = 12.90 : x
  2. Step 2: Convert to fraction form
    13.08/19.74 = 12.90/x
  3. Step 3: Cross multiply
    13.08x = 19.74 × 12.90
  4. Step 4: Simplify right side
    13.08x = 254.65
  5. Step 5: Solve for x
    x = 254.65/13.08
  6. Step 6: Final answer
    x = 19.47

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.