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Finding the Fourth Proportional to 221.34, 305.38 and 138.50

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Solution

The fourth proportional to 221.34, 305.38 and 138.50 is: 191.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.34 : 305.38 = 138.50 : x
  2. Step 2: Convert to fraction form
    221.34/305.38 = 138.50/x
  3. Step 3: Cross multiply
    221.34x = 305.38 × 138.50
  4. Step 4: Simplify right side
    221.34x = 42,294.92
  5. Step 5: Solve for x
    x = 42,294.92/221.34
  6. Step 6: Final answer
    x = 191.08

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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.