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Finding the Fourth Proportional to 511.74, 706.21 and 278.90

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Solution

The fourth proportional to 511.74, 706.21 and 278.90 is: 384.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.74 : 706.21 = 278.90 : x
  2. Step 2: Convert to fraction form
    511.74/706.21 = 278.90/x
  3. Step 3: Cross multiply
    511.74x = 706.21 × 278.90
  4. Step 4: Simplify right side
    511.74x = 196,961.97
  5. Step 5: Solve for x
    x = 196,961.97/511.74
  6. Step 6: Final answer
    x = 384.89

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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.