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Finding the Fourth Proportional to 486.39, 671.13 and 287.28

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Solution

The fourth proportional to 486.39, 671.13 and 287.28 is: 396.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.39 : 671.13 = 287.28 : x
  2. Step 2: Convert to fraction form
    486.39/671.13 = 287.28/x
  3. Step 3: Cross multiply
    486.39x = 671.13 × 287.28
  4. Step 4: Simplify right side
    486.39x = 192,802.23
  5. Step 5: Solve for x
    x = 192,802.23/486.39
  6. Step 6: Final answer
    x = 396.39

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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.