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Finding the Fourth Proportional to 251.78, 347.30 and 212.70

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Solution

The fourth proportional to 251.78, 347.30 and 212.70 is: 293.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    251.78 : 347.30 = 212.70 : x
  2. Step 2: Convert to fraction form
    251.78/347.30 = 212.70/x
  3. Step 3: Cross multiply
    251.78x = 347.30 × 212.70
  4. Step 4: Simplify right side
    251.78x = 73,870.71
  5. Step 5: Solve for x
    x = 73,870.71/251.78
  6. Step 6: Final answer
    x = 293.39

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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.