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Finding the Fourth Proportional to 678.84, 936.84 and 512.79

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Solution

The fourth proportional to 678.84, 936.84 and 512.79 is: 707.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.84 : 936.84 = 512.79 : x
  2. Step 2: Convert to fraction form
    678.84/936.84 = 512.79/x
  3. Step 3: Cross multiply
    678.84x = 936.84 × 512.79
  4. Step 4: Simplify right side
    678.84x = 480,402.18
  5. Step 5: Solve for x
    x = 480,402.18/678.84
  6. Step 6: Final answer
    x = 707.68

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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.