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Finding the Fourth Proportional to 12.65, 18.98 and 3.51

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Solution

The fourth proportional to 12.65, 18.98 and 3.51 is: 5.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    12.65 : 18.98 = 3.51 : x
  2. Step 2: Convert to fraction form
    12.65/18.98 = 3.51/x
  3. Step 3: Cross multiply
    12.65x = 18.98 × 3.51
  4. Step 4: Simplify right side
    12.65x = 66.61
  5. Step 5: Solve for x
    x = 66.61/12.65
  6. Step 6: Final answer
    x = 5.27

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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.