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Finding the Fourth Proportional to 486.09, 670.86 and 289.62

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Solution

The fourth proportional to 486.09, 670.86 and 289.62 is: 399.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.09 : 670.86 = 289.62 : x
  2. Step 2: Convert to fraction form
    486.09/670.86 = 289.62/x
  3. Step 3: Cross multiply
    486.09x = 670.86 × 289.62
  4. Step 4: Simplify right side
    486.09x = 194,294.47
  5. Step 5: Solve for x
    x = 194,294.47/486.09
  6. Step 6: Final answer
    x = 399.71

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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.