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Finding the Fourth Proportional to 290.78, 398.37 and 279.84

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Solution

The fourth proportional to 290.78, 398.37 and 279.84 is: 383.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.78 : 398.37 = 279.84 : x
  2. Step 2: Convert to fraction form
    290.78/398.37 = 279.84/x
  3. Step 3: Cross multiply
    290.78x = 398.37 × 279.84
  4. Step 4: Simplify right side
    290.78x = 111,479.86
  5. Step 5: Solve for x
    x = 111,479.86/290.78
  6. Step 6: Final answer
    x = 383.38

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.