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Finding the Fourth Proportional to 306.56, 423.07 and 219.40

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Solution

The fourth proportional to 306.56, 423.07 and 219.40 is: 302.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.56 : 423.07 = 219.40 : x
  2. Step 2: Convert to fraction form
    306.56/423.07 = 219.40/x
  3. Step 3: Cross multiply
    306.56x = 423.07 × 219.40
  4. Step 4: Simplify right side
    306.56x = 92,819.95
  5. Step 5: Solve for x
    x = 92,819.95/306.56
  6. Step 6: Final answer
    x = 302.78

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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.