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Question
In a certain city there are 30 colleges. Each college has 15 peons, 6 clerks, 1 typist and 1 section officer. Express the given information as a column matrix. Using scalar multiplication, find the total number of posts of each kind in all the colleges.
Solution
Number of different types of posts in any college is given by
`X = [[15],[6],[1],[1]]`
Total number of posts of each kind in all the colleges = 30X
`=30[[15],[6],[1],[1]]`
`=30[[450],[180],[30],[30]]`
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