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Finding the Fourth Proportional to 221.30, 305.40 and 123.05

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Solution

The fourth proportional to 221.30, 305.40 and 123.05 is: 169.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.30 : 305.40 = 123.05 : x
  2. Step 2: Convert to fraction form
    221.30/305.40 = 123.05/x
  3. Step 3: Cross multiply
    221.30x = 305.40 × 123.05
  4. Step 4: Simplify right side
    221.30x = 37,580.23
  5. Step 5: Solve for x
    x = 37,580.23/221.30
  6. Step 6: Final answer
    x = 169.82

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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.