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Finding the Fourth Proportional to 308.96, 426.12 and 210.80

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Solution

The fourth proportional to 308.96, 426.12 and 210.80 is: 290.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.96 : 426.12 = 210.80 : x
  2. Step 2: Convert to fraction form
    308.96/426.12 = 210.80/x
  3. Step 3: Cross multiply
    308.96x = 426.12 × 210.80
  4. Step 4: Simplify right side
    308.96x = 89,826.10
  5. Step 5: Solve for x
    x = 89,826.10/308.96
  6. Step 6: Final answer
    x = 290.74

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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.