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Finding the Fourth Proportional to 210.05, 289.88 and 121.54

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Solution

The fourth proportional to 210.05, 289.88 and 121.54 is: 167.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.05 : 289.88 = 121.54 : x
  2. Step 2: Convert to fraction form
    210.05/289.88 = 121.54/x
  3. Step 3: Cross multiply
    210.05x = 289.88 × 121.54
  4. Step 4: Simplify right side
    210.05x = 35,231.41
  5. Step 5: Solve for x
    x = 35,231.41/210.05
  6. Step 6: Final answer
    x = 167.73

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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.