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प्रश्न
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.
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उत्तर
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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