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Finding the Fourth Proportional to 310.20, 428.14 and 212

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Solution

The fourth proportional to 310.20, 428.14 and 212 is: 292.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    310.20 : 428.14 = 212 : x
  2. Step 2: Convert to fraction form
    310.20/428.14 = 212/x
  3. Step 3: Cross multiply
    310.20x = 428.14 × 212
  4. Step 4: Simplify right side
    310.20x = 90,765.68
  5. Step 5: Solve for x
    x = 90,765.68/310.20
  6. Step 6: Final answer
    x = 292.60

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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.