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Finding the Fourth Proportional to 425.28, 634.30 and 388.84

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Solution

The fourth proportional to 425.28, 634.30 and 388.84 is: 579.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.28 : 634.30 = 388.84 : x
  2. Step 2: Convert to fraction form
    425.28/634.30 = 388.84/x
  3. Step 3: Cross multiply
    425.28x = 634.30 × 388.84
  4. Step 4: Simplify right side
    425.28x = 246,641.21
  5. Step 5: Solve for x
    x = 246,641.21/425.28
  6. Step 6: Final answer
    x = 579.95

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.