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Finding the Fourth Proportional to 391.01, 539.21 and 278.93

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Solution

The fourth proportional to 391.01, 539.21 and 278.93 is: 384.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.01 : 539.21 = 278.93 : x
  2. Step 2: Convert to fraction form
    391.01/539.21 = 278.93/x
  3. Step 3: Cross multiply
    391.01x = 539.21 × 278.93
  4. Step 4: Simplify right side
    391.01x = 150,403.89
  5. Step 5: Solve for x
    x = 150,403.89/391.01
  6. Step 6: Final answer
    x = 384.66

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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.