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Finding the Fourth Proportional to 418.94, 578.30 and 288.39

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Solution

The fourth proportional to 418.94, 578.30 and 288.39 is: 398.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.94 : 578.30 = 288.39 : x
  2. Step 2: Convert to fraction form
    418.94/578.30 = 288.39/x
  3. Step 3: Cross multiply
    418.94x = 578.30 × 288.39
  4. Step 4: Simplify right side
    418.94x = 166,774.50
  5. Step 5: Solve for x
    x = 166,774.50/418.94
  6. Step 6: Final answer
    x = 398.09

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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.