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Finding the Fourth Proportional to 308.87, 426.53 and 279.71

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Solution

The fourth proportional to 308.87, 426.53 and 279.71 is: 386.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.87 : 426.53 = 279.71 : x
  2. Step 2: Convert to fraction form
    308.87/426.53 = 279.71/x
  3. Step 3: Cross multiply
    308.87x = 426.53 × 279.71
  4. Step 4: Simplify right side
    308.87x = 119,304.71
  5. Step 5: Solve for x
    x = 119,304.71/308.87
  6. Step 6: Final answer
    x = 386.26

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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.