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Finding the Fourth Proportional to 289.80, 400.41 and 279.43

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Solution

The fourth proportional to 289.80, 400.41 and 279.43 is: 386.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.80 : 400.41 = 279.43 : x
  2. Step 2: Convert to fraction form
    289.80/400.41 = 279.43/x
  3. Step 3: Cross multiply
    289.80x = 400.41 × 279.43
  4. Step 4: Simplify right side
    289.80x = 111,885.57
  5. Step 5: Solve for x
    x = 111,885.57/289.80
  6. Step 6: Final answer
    x = 386.08

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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.