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Finding the Fourth Proportional to 221.40, 305.10 and 213.30

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Solution

The fourth proportional to 221.40, 305.10 and 213.30 is: 293.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.40 : 305.10 = 213.30 : x
  2. Step 2: Convert to fraction form
    221.40/305.10 = 213.30/x
  3. Step 3: Cross multiply
    221.40x = 305.10 × 213.30
  4. Step 4: Simplify right side
    221.40x = 65,077.83
  5. Step 5: Solve for x
    x = 65,077.83/221.40
  6. Step 6: Final answer
    x = 293.94

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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.