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Finding the Fourth Proportional to 613.10, 845.74 and 391.80

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Solution

The fourth proportional to 613.10, 845.74 and 391.80 is: 540.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.10 : 845.74 = 391.80 : x
  2. Step 2: Convert to fraction form
    613.10/845.74 = 391.80/x
  3. Step 3: Cross multiply
    613.10x = 845.74 × 391.80
  4. Step 4: Simplify right side
    613.10x = 331,360.93
  5. Step 5: Solve for x
    x = 331,360.93/613.10
  6. Step 6: Final answer
    x = 540.47

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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.