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Finding the Fourth Proportional to 308.40, 426.03 and 215.40

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Solution

The fourth proportional to 308.40, 426.03 and 215.40 is: 297.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.40 : 426.03 = 215.40 : x
  2. Step 2: Convert to fraction form
    308.40/426.03 = 215.40/x
  3. Step 3: Cross multiply
    308.40x = 426.03 × 215.40
  4. Step 4: Simplify right side
    308.40x = 91,766.86
  5. Step 5: Solve for x
    x = 91,766.86/308.40
  6. Step 6: Final answer
    x = 297.56

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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.