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Finding the Fourth Proportional to 286.61, 428.69 and 170.78

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Solution

The fourth proportional to 286.61, 428.69 and 170.78 is: 255.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.61 : 428.69 = 170.78 : x
  2. Step 2: Convert to fraction form
    286.61/428.69 = 170.78/x
  3. Step 3: Cross multiply
    286.61x = 428.69 × 170.78
  4. Step 4: Simplify right side
    286.61x = 73,209.96
  5. Step 5: Solve for x
    x = 73,209.96/286.61
  6. Step 6: Final answer
    x = 255.44

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.