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Finding the Fourth Proportional to 221.05, 305.10 and 127.79

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Solution

The fourth proportional to 221.05, 305.10 and 127.79 is: 176.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.05 : 305.10 = 127.79 : x
  2. Step 2: Convert to fraction form
    221.05/305.10 = 127.79/x
  3. Step 3: Cross multiply
    221.05x = 305.10 × 127.79
  4. Step 4: Simplify right side
    221.05x = 38,989.47
  5. Step 5: Solve for x
    x = 38,989.47/221.05
  6. Step 6: Final answer
    x = 176.38

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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.