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Finding the Fourth Proportional to 219.79, 303.31 and 121.56

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Solution

The fourth proportional to 219.79, 303.31 and 121.56 is: 167.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    219.79 : 303.31 = 121.56 : x
  2. Step 2: Convert to fraction form
    219.79/303.31 = 121.56/x
  3. Step 3: Cross multiply
    219.79x = 303.31 × 121.56
  4. Step 4: Simplify right side
    219.79x = 36,869.38
  5. Step 5: Solve for x
    x = 36,869.38/219.79
  6. Step 6: Final answer
    x = 167.75

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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.