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Finding the Fourth Proportional to 418.42, 624.56 and 388.39

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Solution

The fourth proportional to 418.42, 624.56 and 388.39 is: 579.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.42 : 624.56 = 388.39 : x
  2. Step 2: Convert to fraction form
    418.42/624.56 = 388.39/x
  3. Step 3: Cross multiply
    418.42x = 624.56 × 388.39
  4. Step 4: Simplify right side
    418.42x = 242,572.86
  5. Step 5: Solve for x
    x = 242,572.86/418.42
  6. Step 6: Final answer
    x = 579.74

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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.