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Finding the Fourth Proportional to 281.90, 389.07 and 208.60

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Solution

The fourth proportional to 281.90, 389.07 and 208.60 is: 287.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.90 : 389.07 = 208.60 : x
  2. Step 2: Convert to fraction form
    281.90/389.07 = 208.60/x
  3. Step 3: Cross multiply
    281.90x = 389.07 × 208.60
  4. Step 4: Simplify right side
    281.90x = 81,160.00
  5. Step 5: Solve for x
    x = 81,160.00/281.90
  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.