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Finding the Fourth Proportional to 279.91, 420.19 and 203.31

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Solution

The fourth proportional to 279.91, 420.19 and 203.31 is: 305.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.91 : 420.19 = 203.31 : x
  2. Step 2: Convert to fraction form
    279.91/420.19 = 203.31/x
  3. Step 3: Cross multiply
    279.91x = 420.19 × 203.31
  4. Step 4: Simplify right side
    279.91x = 85,428.32
  5. Step 5: Solve for x
    x = 85,428.32/279.91
  6. Step 6: Final answer
    x = 305.20

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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.