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Finding the Fourth Proportional to 221.40, 306.30 and 216.60

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Solution

The fourth proportional to 221.40, 306.30 and 216.60 is: 299.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    221.40 : 306.30 = 216.60 : x
  2. Step 2: Convert to fraction form
    221.40/306.30 = 216.60/x
  3. Step 3: Cross multiply
    221.40x = 306.30 × 216.60
  4. Step 4: Simplify right side
    221.40x = 66,344.58
  5. Step 5: Solve for x
    x = 66,344.58/221.40
  6. Step 6: Final answer
    x = 299.66

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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.