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Finding the Fourth Proportional to 671.81, 1,007.79 and 209.51

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Solution

The fourth proportional to 671.81, 1,007.79 and 209.51 is: 314.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    671.81 : 1,007.79 = 209.51 : x
  2. Step 2: Convert to fraction form
    671.81/1,007.79 = 209.51/x
  3. Step 3: Cross multiply
    671.81x = 1,007.79 × 209.51
  4. Step 4: Simplify right side
    671.81x = 211,142.08
  5. Step 5: Solve for x
    x = 211,142.08/671.81
  6. Step 6: Final answer
    x = 314.29

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.