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Finding the Fourth Proportional to 287.69, 395.82 and 279.99

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Solution

The fourth proportional to 287.69, 395.82 and 279.99 is: 385.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.69 : 395.82 = 279.99 : x
  2. Step 2: Convert to fraction form
    287.69/395.82 = 279.99/x
  3. Step 3: Cross multiply
    287.69x = 395.82 × 279.99
  4. Step 4: Simplify right side
    287.69x = 110,825.64
  5. Step 5: Solve for x
    x = 110,825.64/287.69
  6. Step 6: Final answer
    x = 385.23

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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.