हिंदी

In a class, there are 27 boys and 14 girls. The teacher wants to select 1 boy and 1 girl to represent the class for a function. In how many ways can the teacher make this selection?

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प्रश्न

In a class, there are 27 boys and 14 girls. The teacher wants to select 1 boy and 1 girl to represent the class for a function. In how many ways can the teacher make this selection?

योग
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उत्तर

Here the teacher is to perform two operations:

(i) Selecting a boy from among the 27 boys and

(ii) Selecting a girl from among 14 girls.

The first of these can be done in 27 ways and second can be performed in 14 ways.

By the fundamental principle of counting, the required number of ways is 27 × 14 = 378.

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अध्याय 7: Permutations and Combinations - Solved Examples [पृष्ठ ११५]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 11
अध्याय 7 Permutations and Combinations
Solved Examples | Q 1 | पृष्ठ ११५

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