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Finding the Fourth Proportional to 216.30, 298.39 and 138.63

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Solution

The fourth proportional to 216.30, 298.39 and 138.63 is: 191.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    216.30 : 298.39 = 138.63 : x
  2. Step 2: Convert to fraction form
    216.30/298.39 = 138.63/x
  3. Step 3: Cross multiply
    216.30x = 298.39 × 138.63
  4. Step 4: Simplify right side
    216.30x = 41,365.81
  5. Step 5: Solve for x
    x = 41,365.81/216.30
  6. Step 6: Final answer
    x = 191.24

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.