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Finding the Fourth Proportional to 221.30, 305.39 and 155.94

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Solution

The fourth proportional to 221.30, 305.39 and 155.94 is: 215.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.30 : 305.39 = 155.94 : x
  2. Step 2: Convert to fraction form
    221.30/305.39 = 155.94/x
  3. Step 3: Cross multiply
    221.30x = 305.39 × 155.94
  4. Step 4: Simplify right side
    221.30x = 47,622.32
  5. Step 5: Solve for x
    x = 47,622.32/221.30
  6. Step 6: Final answer
    x = 215.19

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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.