Try this solution with short explanation; note, the suggested way is not the shortest one; the answers are marked with red colour.
Task no. 2: another solution is 45* (4/5) / (6/4) = 24 min.
The combination expression that demonstrates how the 20 is calculated using the combination pattern is 6C3
<h3>Permutation and Combination</h3>
While combination has to do with selection, permutation has to do with arrangement.
According to the combination rule
nCr = n!/(n-r)!r!
The expression that gives the result of 20 is expressed below;
6C3 = 6!/(6-3)!3!
6C3 = 6!/3!3!
6C3 = 6!/6*6
6C3 = 720/36
6C3 =20
Hence the combination expression that demonstrates how the 20 is calculated using the combination pattern is 6C3
Learn more on combination here: brainly.com/question/4658834
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