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Finding the Fourth Proportional to 486.98, 671.49 and 320.90

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Solution

The fourth proportional to 486.98, 671.49 and 320.90 is: 442.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.98 : 671.49 = 320.90 : x
  2. Step 2: Convert to fraction form
    486.98/671.49 = 320.90/x
  3. Step 3: Cross multiply
    486.98x = 671.49 × 320.90
  4. Step 4: Simplify right side
    486.98x = 215,477.78
  5. Step 5: Solve for x
    x = 215,477.78/486.98
  6. Step 6: Final answer
    x = 442.48

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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.