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Finding the Fourth Proportional to 312.03, 430.02 and 280.62

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Solution

The fourth proportional to 312.03, 430.02 and 280.62 is: 386.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.03 : 430.02 = 280.62 : x
  2. Step 2: Convert to fraction form
    312.03/430.02 = 280.62/x
  3. Step 3: Cross multiply
    312.03x = 430.02 × 280.62
  4. Step 4: Simplify right side
    312.03x = 120,672.21
  5. Step 5: Solve for x
    x = 120,672.21/312.03
  6. Step 6: Final answer
    x = 386.73

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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.