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Finding the Fourth Proportional to 306.90, 423.54 and 213.60

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Solution

The fourth proportional to 306.90, 423.54 and 213.60 is: 294.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.90 : 423.54 = 213.60 : x
  2. Step 2: Convert to fraction form
    306.90/423.54 = 213.60/x
  3. Step 3: Cross multiply
    306.90x = 423.54 × 213.60
  4. Step 4: Simplify right side
    306.90x = 90,468.14
  5. Step 5: Solve for x
    x = 90,468.14/306.90
  6. Step 6: Final answer
    x = 294.78

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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.