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Finding the Fourth Proportional to 279.47, 385.61 and 205.80

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Solution

The fourth proportional to 279.47, 385.61 and 205.80 is: 283.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.47 : 385.61 = 205.80 : x
  2. Step 2: Convert to fraction form
    279.47/385.61 = 205.80/x
  3. Step 3: Cross multiply
    279.47x = 385.61 × 205.80
  4. Step 4: Simplify right side
    279.47x = 79,357.51
  5. Step 5: Solve for x
    x = 79,357.51/279.47
  6. Step 6: Final answer
    x = 283.96

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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.