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Finding the Fourth Proportional to 305.31, 421.53 and 201.87

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Solution

The fourth proportional to 305.31, 421.53 and 201.87 is: 278.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.31 : 421.53 = 201.87 : x
  2. Step 2: Convert to fraction form
    305.31/421.53 = 201.87/x
  3. Step 3: Cross multiply
    305.31x = 421.53 × 201.87
  4. Step 4: Simplify right side
    305.31x = 85,094.26
  5. Step 5: Solve for x
    x = 85,094.26/305.31
  6. Step 6: Final answer
    x = 278.71

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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.