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Finding the Fourth Proportional to 486.57, 671.19 and 309.21

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Solution

The fourth proportional to 486.57, 671.19 and 309.21 is: 426.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.57 : 671.19 = 309.21 : x
  2. Step 2: Convert to fraction form
    486.57/671.19 = 309.21/x
  3. Step 3: Cross multiply
    486.57x = 671.19 × 309.21
  4. Step 4: Simplify right side
    486.57x = 207,538.66
  5. Step 5: Solve for x
    x = 207,538.66/486.57
  6. Step 6: Final answer
    x = 426.53

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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.