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Finding the Fourth Proportional to 413.79, 620.31 and 208.07

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Solution

The fourth proportional to 413.79, 620.31 and 208.07 is: 311.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    413.79 : 620.31 = 208.07 : x
  2. Step 2: Convert to fraction form
    413.79/620.31 = 208.07/x
  3. Step 3: Cross multiply
    413.79x = 620.31 × 208.07
  4. Step 4: Simplify right side
    413.79x = 129,064.80
  5. Step 5: Solve for x
    x = 129,064.80/413.79
  6. Step 6: Final answer
    x = 311.91

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.