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Finding the Fourth Proportional to 289.09, 398.67 and 247.78

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Solution

The fourth proportional to 289.09, 398.67 and 247.78 is: 341.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.09 : 398.67 = 247.78 : x
  2. Step 2: Convert to fraction form
    289.09/398.67 = 247.78/x
  3. Step 3: Cross multiply
    289.09x = 398.67 × 247.78
  4. Step 4: Simplify right side
    289.09x = 98,782.45
  5. Step 5: Solve for x
    x = 98,782.45/289.09
  6. Step 6: Final answer
    x = 341.70

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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.