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Finding the Fourth Proportional to 678.87, 936.80 and 413.28

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Solution

The fourth proportional to 678.87, 936.80 and 413.28 is: 570.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.87 : 936.80 = 413.28 : x
  2. Step 2: Convert to fraction form
    678.87/936.80 = 413.28/x
  3. Step 3: Cross multiply
    678.87x = 936.80 × 413.28
  4. Step 4: Simplify right side
    678.87x = 387,160.19
  5. Step 5: Solve for x
    x = 387,160.19/678.87
  6. Step 6: Final answer
    x = 570.30

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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.