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Finding the Fourth Proportional to 486.86, 671.72 and 290.34

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Solution

The fourth proportional to 486.86, 671.72 and 290.34 is: 400.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.86 : 671.72 = 290.34 : x
  2. Step 2: Convert to fraction form
    486.86/671.72 = 290.34/x
  3. Step 3: Cross multiply
    486.86x = 671.72 × 290.34
  4. Step 4: Simplify right side
    486.86x = 195,025.73
  5. Step 5: Solve for x
    x = 195,025.73/486.86
  6. Step 6: Final answer
    x = 400.58

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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.