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Finding the Fourth Proportional to 311.18, 428.86 and 302.29

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Solution

The fourth proportional to 311.18, 428.86 and 302.29 is: 416.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    311.18 : 428.86 = 302.29 : x
  2. Step 2: Convert to fraction form
    311.18/428.86 = 302.29/x
  3. Step 3: Cross multiply
    311.18x = 428.86 × 302.29
  4. Step 4: Simplify right side
    311.18x = 129,640.09
  5. Step 5: Solve for x
    x = 129,640.09/311.18
  6. Step 6: Final answer
    x = 416.61

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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.