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Finding the Fourth Proportional to 287.87, 397.03 and 209.19

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Solution

The fourth proportional to 287.87, 397.03 and 209.19 is: 288.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.87 : 397.03 = 209.19 : x
  2. Step 2: Convert to fraction form
    287.87/397.03 = 209.19/x
  3. Step 3: Cross multiply
    287.87x = 397.03 × 209.19
  4. Step 4: Simplify right side
    287.87x = 83,053.66
  5. Step 5: Solve for x
    x = 83,053.66/287.87
  6. Step 6: Final answer
    x = 288.51

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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.