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Finding the Fourth Proportional to 308.79, 426.30 and 210.69

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Solution

The fourth proportional to 308.79, 426.30 and 210.69 is: 290.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.79 : 426.30 = 210.69 : x
  2. Step 2: Convert to fraction form
    308.79/426.30 = 210.69/x
  3. Step 3: Cross multiply
    308.79x = 426.30 × 210.69
  4. Step 4: Simplify right side
    308.79x = 89,817.15
  5. Step 5: Solve for x
    x = 89,817.15/308.79
  6. Step 6: Final answer
    x = 290.87

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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.