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Finding the Fourth Proportional to 308.80, 426.18 and 298.72

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Solution

The fourth proportional to 308.80, 426.18 and 298.72 is: 412.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.80 : 426.18 = 298.72 : x
  2. Step 2: Convert to fraction form
    308.80/426.18 = 298.72/x
  3. Step 3: Cross multiply
    308.80x = 426.18 × 298.72
  4. Step 4: Simplify right side
    308.80x = 127,308.49
  5. Step 5: Solve for x
    x = 127,308.49/308.80
  6. Step 6: Final answer
    x = 412.27

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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.