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Smog is a type of air pollution; the word "smog" was coined in the early 20th century as a portmanteau of the words smoke and fog to refer to smoky fog. The word was then intended to refer to what was sometimes known as pea soup fog, a familiar and serious problem in London from the 19th century to the mid 20th century. This kind of smog is caused by the burning of large amounts of coal within a city; this smog contains soot particulates from smoke, sulfur dioxide and other components.
The average age of three children is 32 years. If their ages are in the ratio 3:6:7. Find the age of the youngest child.
The average of the first 7 non-zero multiples of 18 is:
The average of 11 observations is 60. If the average of first five observations is 58 and that of last five is 56, the sixth observation is
The average of five numbers is 30. If one of the numbers is removed, the average becomes 25. What is the number that was removed?