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Finding the Fourth Proportional to 279.71, 419.71 and 211.65

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Solution

The fourth proportional to 279.71, 419.71 and 211.65 is: 317.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.71 : 419.71 = 211.65 : x
  2. Step 2: Convert to fraction form
    279.71/419.71 = 211.65/x
  3. Step 3: Cross multiply
    279.71x = 419.71 × 211.65
  4. Step 4: Simplify right side
    279.71x = 88,833.20
  5. Step 5: Solve for x
    x = 88,833.20/279.71
  6. Step 6: Final answer
    x = 317.59

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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.