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Finding the Fourth Proportional to 807.26, 1,211 and 287.21

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Solution

The fourth proportional to 807.26, 1,211 and 287.21 is: 430.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.26 : 1,211 = 287.21 : x
  2. Step 2: Convert to fraction form
    807.26/1,211 = 287.21/x
  3. Step 3: Cross multiply
    807.26x = 1,211 × 287.21
  4. Step 4: Simplify right side
    807.26x = 347,811.31
  5. Step 5: Solve for x
    x = 347,811.31/807.26
  6. Step 6: Final answer
    x = 430.86

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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.