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Finding the Fourth Proportional to 281.80, 389.37 and 208.36

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Solution

The fourth proportional to 281.80, 389.37 and 208.36 is: 287.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.80 : 389.37 = 208.36 : x
  2. Step 2: Convert to fraction form
    281.80/389.37 = 208.36/x
  3. Step 3: Cross multiply
    281.80x = 389.37 × 208.36
  4. Step 4: Simplify right side
    281.80x = 81,129.13
  5. Step 5: Solve for x
    x = 81,129.13/281.80
  6. Step 6: Final answer
    x = 287.90

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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.