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Finding the Fourth Proportional to 486.87, 671.84 and 287.72

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Solution

The fourth proportional to 486.87, 671.84 and 287.72 is: 397.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.87 : 671.84 = 287.72 : x
  2. Step 2: Convert to fraction form
    486.87/671.84 = 287.72/x
  3. Step 3: Cross multiply
    486.87x = 671.84 × 287.72
  4. Step 4: Simplify right side
    486.87x = 193,301.80
  5. Step 5: Solve for x
    x = 193,301.80/486.87
  6. Step 6: Final answer
    x = 397.03

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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.