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Finding the Fourth Proportional to 286.76, 428.05 and 259.56

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Solution

The fourth proportional to 286.76, 428.05 and 259.56 is: 387.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.76 : 428.05 = 259.56 : x
  2. Step 2: Convert to fraction form
    286.76/428.05 = 259.56/x
  3. Step 3: Cross multiply
    286.76x = 428.05 × 259.56
  4. Step 4: Simplify right side
    286.76x = 111,104.66
  5. Step 5: Solve for x
    x = 111,104.66/286.76
  6. Step 6: Final answer
    x = 387.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.