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Finding the Fourth Proportional to 303.85, 421.24 and 287.43

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Solution

The fourth proportional to 303.85, 421.24 and 287.43 is: 398.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    303.85 : 421.24 = 287.43 : x
  2. Step 2: Convert to fraction form
    303.85/421.24 = 287.43/x
  3. Step 3: Cross multiply
    303.85x = 421.24 × 287.43
  4. Step 4: Simplify right side
    303.85x = 121,077.01
  5. Step 5: Solve for x
    x = 121,077.01/303.85
  6. Step 6: Final answer
    x = 398.48

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.