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Finding the Fourth Proportional to 678.83, 936.86 and 512.78

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Solution

The fourth proportional to 678.83, 936.86 and 512.78 is: 707.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.83 : 936.86 = 512.78 : x
  2. Step 2: Convert to fraction form
    678.83/936.86 = 512.78/x
  3. Step 3: Cross multiply
    678.83x = 936.86 × 512.78
  4. Step 4: Simplify right side
    678.83x = 480,395.82
  5. Step 5: Solve for x
    x = 480,395.82/678.83
  6. Step 6: Final answer
    x = 707.69

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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.