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Finding the Fourth Proportional to 511.45, 705.78 and 278.57

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Solution

The fourth proportional to 511.45, 705.78 and 278.57 is: 384.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.45 : 705.78 = 278.57 : x
  2. Step 2: Convert to fraction form
    511.45/705.78 = 278.57/x
  3. Step 3: Cross multiply
    511.45x = 705.78 × 278.57
  4. Step 4: Simplify right side
    511.45x = 196,609.13
  5. Step 5: Solve for x
    x = 196,609.13/511.45
  6. Step 6: Final answer
    x = 384.42

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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.