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Finding the Fourth Proportional to 279.90, 385.86 and 213.50

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Solution

The fourth proportional to 279.90, 385.86 and 213.50 is: 294.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.90 : 385.86 = 213.50 : x
  2. Step 2: Convert to fraction form
    279.90/385.86 = 213.50/x
  3. Step 3: Cross multiply
    279.90x = 385.86 × 213.50
  4. Step 4: Simplify right side
    279.90x = 82,382.88
  5. Step 5: Solve for x
    x = 82,382.88/279.90
  6. Step 6: Final answer
    x = 294.33

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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.