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Finding the Fourth Proportional to 280.65, 419.91 and 211.11

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Solution

The fourth proportional to 280.65, 419.91 and 211.11 is: 315.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.65 : 419.91 = 211.11 : x
  2. Step 2: Convert to fraction form
    280.65/419.91 = 211.11/x
  3. Step 3: Cross multiply
    280.65x = 419.91 × 211.11
  4. Step 4: Simplify right side
    280.65x = 88,647.20
  5. Step 5: Solve for x
    x = 88,647.20/280.65
  6. Step 6: Final answer
    x = 315.86

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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.