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Finding the Fourth Proportional to 313.38, 432.64 and 278.78

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Solution

The fourth proportional to 313.38, 432.64 and 278.78 is: 384.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    313.38 : 432.64 = 278.78 : x
  2. Step 2: Convert to fraction form
    313.38/432.64 = 278.78/x
  3. Step 3: Cross multiply
    313.38x = 432.64 × 278.78
  4. Step 4: Simplify right side
    313.38x = 120,609.56
  5. Step 5: Solve for x
    x = 120,609.56/313.38
  6. Step 6: Final answer
    x = 384.87

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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.