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Finding the Fourth Proportional to 486.85, 671.61 and 309.51

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Solution

The fourth proportional to 486.85, 671.61 and 309.51 is: 426.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.85 : 671.61 = 309.51 : x
  2. Step 2: Convert to fraction form
    486.85/671.61 = 309.51/x
  3. Step 3: Cross multiply
    486.85x = 671.61 × 309.51
  4. Step 4: Simplify right side
    486.85x = 207,870.01
  5. Step 5: Solve for x
    x = 207,870.01/486.85
  6. Step 6: Final answer
    x = 426.97

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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.