if three straws are chosen at random from a set of 8 straws whose lengths are 1cm, 2cm 3cm, 4cm, 5cm 6cm, 7cm, and 8cm find the probability that the three straws will form a triangle.
This is similar to the following question: https://web2.0calc.com/questions/if-three-straws-are-chosen-at-random-from-a-set-of-9-straws
The total number of ways to pick the 3 straws = $8 \choose {3}$ $ = 56,$ so the total is 56. See if you can find the favorable on your own :)