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Finding the Fourth Proportional to 418.09, 627.08 and 212.81

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Solution

The fourth proportional to 418.09, 627.08 and 212.81 is: 319.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.09 : 627.08 = 212.81 : x
  2. Step 2: Convert to fraction form
    418.09/627.08 = 212.81/x
  3. Step 3: Cross multiply
    418.09x = 627.08 × 212.81
  4. Step 4: Simplify right side
    418.09x = 133,446.80
  5. Step 5: Solve for x
    x = 133,446.80/418.09
  6. Step 6: Final answer
    x = 319.18

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.