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Finding the Fourth Proportional to 312.08, 430.79 and 279.27

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Solution

The fourth proportional to 312.08, 430.79 and 279.27 is: 385.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.08 : 430.79 = 279.27 : x
  2. Step 2: Convert to fraction form
    312.08/430.79 = 279.27/x
  3. Step 3: Cross multiply
    312.08x = 430.79 × 279.27
  4. Step 4: Simplify right side
    312.08x = 120,305.33
  5. Step 5: Solve for x
    x = 120,305.33/312.08
  6. Step 6: Final answer
    x = 385.50

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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.