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Finding the Fourth Proportional to 282.87, 390.30 and 208.30

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Solution

The fourth proportional to 282.87, 390.30 and 208.30 is: 287.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    282.87 : 390.30 = 208.30 : x
  2. Step 2: Convert to fraction form
    282.87/390.30 = 208.30/x
  3. Step 3: Cross multiply
    282.87x = 390.30 × 208.30
  4. Step 4: Simplify right side
    282.87x = 81,299.49
  5. Step 5: Solve for x
    x = 81,299.49/282.87
  6. Step 6: Final answer
    x = 287.41

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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.