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Finding the Fourth Proportional to 486.15, 670.68 and 309.05

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Solution

The fourth proportional to 486.15, 670.68 and 309.05 is: 426.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.15 : 670.68 = 309.05 : x
  2. Step 2: Convert to fraction form
    486.15/670.68 = 309.05/x
  3. Step 3: Cross multiply
    486.15x = 670.68 × 309.05
  4. Step 4: Simplify right side
    486.15x = 207,270.30
  5. Step 5: Solve for x
    x = 207,270.30/486.15
  6. Step 6: Final answer
    x = 426.35

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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.