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Finding the Fourth Proportional to 418.40, 578.16 and 320.84

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Solution

The fourth proportional to 418.40, 578.16 and 320.84 is: 443.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.40 : 578.16 = 320.84 : x
  2. Step 2: Convert to fraction form
    418.40/578.16 = 320.84/x
  3. Step 3: Cross multiply
    418.40x = 578.16 × 320.84
  4. Step 4: Simplify right side
    418.40x = 185,493.96
  5. Step 5: Solve for x
    x = 185,493.96/418.40
  6. Step 6: Final answer
    x = 443.35

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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.