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Finding the Fourth Proportional to 308.40, 426.04 and 285.36

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Solution

The fourth proportional to 308.40, 426.04 and 285.36 is: 394.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.40 : 426.04 = 285.36 : x
  2. Step 2: Convert to fraction form
    308.40/426.04 = 285.36/x
  3. Step 3: Cross multiply
    308.40x = 426.04 × 285.36
  4. Step 4: Simplify right side
    308.40x = 121,574.77
  5. Step 5: Solve for x
    x = 121,574.77/308.40
  6. Step 6: Final answer
    x = 394.21

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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.