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Finding the Fourth Proportional to 279.75, 419.31 and 211.05

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Solution

The fourth proportional to 279.75, 419.31 and 211.05 is: 316.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.75 : 419.31 = 211.05 : x
  2. Step 2: Convert to fraction form
    279.75/419.31 = 211.05/x
  3. Step 3: Cross multiply
    279.75x = 419.31 × 211.05
  4. Step 4: Simplify right side
    279.75x = 88,495.38
  5. Step 5: Solve for x
    x = 88,495.38/279.75
  6. Step 6: Final answer
    x = 316.34

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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.