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Finding the Fourth Proportional to 486.85, 671.91 and 290.36

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Solution

The fourth proportional to 486.85, 671.91 and 290.36 is: 400.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.85 : 671.91 = 290.36 : x
  2. Step 2: Convert to fraction form
    486.85/671.91 = 290.36/x
  3. Step 3: Cross multiply
    486.85x = 671.91 × 290.36
  4. Step 4: Simplify right side
    486.85x = 195,095.79
  5. Step 5: Solve for x
    x = 195,095.79/486.85
  6. Step 6: Final answer
    x = 400.73

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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.