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Finding the Fourth Proportional to 485.82, 670.40 and 308.74

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Solution

The fourth proportional to 485.82, 670.40 and 308.74 is: 426.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.82 : 670.40 = 308.74 : x
  2. Step 2: Convert to fraction form
    485.82/670.40 = 308.74/x
  3. Step 3: Cross multiply
    485.82x = 670.40 × 308.74
  4. Step 4: Simplify right side
    485.82x = 206,979.30
  5. Step 5: Solve for x
    x = 206,979.30/485.82
  6. Step 6: Final answer
    x = 426.04

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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.