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Finding the Fourth Proportional to 210.20, 289.98 and 122.72

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Solution

The fourth proportional to 210.20, 289.98 and 122.72 is: 169.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.20 : 289.98 = 122.72 : x
  2. Step 2: Convert to fraction form
    210.20/289.98 = 122.72/x
  3. Step 3: Cross multiply
    210.20x = 289.98 × 122.72
  4. Step 4: Simplify right side
    210.20x = 35,584.90
  5. Step 5: Solve for x
    x = 35,584.90/210.20
  6. Step 6: Final answer
    x = 169.29

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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.