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Finding the Fourth Proportional to 486.31, 670.87 and 287.08

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Solution

The fourth proportional to 486.31, 670.87 and 287.08 is: 396.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.31 : 670.87 = 287.08 : x
  2. Step 2: Convert to fraction form
    486.31/670.87 = 287.08/x
  3. Step 3: Cross multiply
    486.31x = 670.87 × 287.08
  4. Step 4: Simplify right side
    486.31x = 192,593.36
  5. Step 5: Solve for x
    x = 192,593.36/486.31
  6. Step 6: Final answer
    x = 396.03

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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.