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Finding the Fourth Proportional to 289.40, 398.81 and 270.86

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Solution

The fourth proportional to 289.40, 398.81 and 270.86 is: 373.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.40 : 398.81 = 270.86 : x
  2. Step 2: Convert to fraction form
    289.40/398.81 = 270.86/x
  3. Step 3: Cross multiply
    289.40x = 398.81 × 270.86
  4. Step 4: Simplify right side
    289.40x = 108,018.33
  5. Step 5: Solve for x
    x = 108,018.33/289.40
  6. Step 6: Final answer
    x = 373.26

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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.