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Finding the Fourth Proportional to 221.30, 330.03 and 218.90

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Solution

The fourth proportional to 221.30, 330.03 and 218.90 is: 326.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.30 : 330.03 = 218.90 : x
  2. Step 2: Convert to fraction form
    221.30/330.03 = 218.90/x
  3. Step 3: Cross multiply
    221.30x = 330.03 × 218.90
  4. Step 4: Simplify right side
    221.30x = 72,242.47
  5. Step 5: Solve for x
    x = 72,242.47/221.30
  6. Step 6: Final answer
    x = 326.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.