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Finding the Fourth Proportional to 221.13, 305.13 and 121.53

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Solution

The fourth proportional to 221.13, 305.13 and 121.53 is: 167.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.13 : 305.13 = 121.53 : x
  2. Step 2: Convert to fraction form
    221.13/305.13 = 121.53/x
  3. Step 3: Cross multiply
    221.13x = 305.13 × 121.53
  4. Step 4: Simplify right side
    221.13x = 37,082.45
  5. Step 5: Solve for x
    x = 37,082.45/221.13
  6. Step 6: Final answer
    x = 167.70

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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.