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Finding the Fourth Proportional to 390.30, 537.87 and 279.59

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Solution

The fourth proportional to 390.30, 537.87 and 279.59 is: 385.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.30 : 537.87 = 279.59 : x
  2. Step 2: Convert to fraction form
    390.30/537.87 = 279.59/x
  3. Step 3: Cross multiply
    390.30x = 537.87 × 279.59
  4. Step 4: Simplify right side
    390.30x = 150,380.38
  5. Step 5: Solve for x
    x = 150,380.38/390.30
  6. Step 6: Final answer
    x = 385.29

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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.