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Finding the Fourth Proportional to 668.91, 922.89 and 389.09

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Solution

The fourth proportional to 668.91, 922.89 and 389.09 is: 536.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.91 : 922.89 = 389.09 : x
  2. Step 2: Convert to fraction form
    668.91/922.89 = 389.09/x
  3. Step 3: Cross multiply
    668.91x = 922.89 × 389.09
  4. Step 4: Simplify right side
    668.91x = 359,089.58
  5. Step 5: Solve for x
    x = 359,089.58/668.91
  6. Step 6: Final answer
    x = 536.83

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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.