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Finding the Fourth Proportional to 678.65, 936.38 and 413.09

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Solution

The fourth proportional to 678.65, 936.38 and 413.09 is: 569.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.65 : 936.38 = 413.09 : x
  2. Step 2: Convert to fraction form
    678.65/936.38 = 413.09/x
  3. Step 3: Cross multiply
    678.65x = 936.38 × 413.09
  4. Step 4: Simplify right side
    678.65x = 386,802.47
  5. Step 5: Solve for x
    x = 386,802.47/678.65
  6. Step 6: Final answer
    x = 569.96

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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.