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Finding the Fourth Proportional to 276.90, 381.87 and 221.64

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Solution

The fourth proportional to 276.90, 381.87 and 221.64 is: 305.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    276.90 : 381.87 = 221.64 : x
  2. Step 2: Convert to fraction form
    276.90/381.87 = 221.64/x
  3. Step 3: Cross multiply
    276.90x = 381.87 × 221.64
  4. Step 4: Simplify right side
    276.90x = 84,637.67
  5. Step 5: Solve for x
    x = 84,637.67/276.90
  6. Step 6: Final answer
    x = 305.66

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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.