a; \(\dfrac{1919}{2121}\) = \(\dfrac{1919:101}{2121:101}\) = \(\dfrac{19}{21}\)
b; 17 x 5 - \(\dfrac{17}{120}\) - 103
= 85 - \(\dfrac{17}{120}\) - 103
= \(\dfrac{10200}{120}\) - \(\dfrac{17}{120}\) - \(\dfrac{12360}{120}\)
= \(\dfrac{10183}{120}\) - \(\dfrac{12360}{120}\)
= \(\dfrac{-2177}{120}\)
c; 2929 - \(\dfrac{101}{2\times1919}\) + 404
= 2929 - \(\dfrac{1}{38}\) + 404
= \(\dfrac{111302}{38}\) - \(\dfrac{1}{38}\) + \(\dfrac{15352}{38}\)
= \(\dfrac{111301}{38}\) + \(\dfrac{15352}{38}\)
= \(\dfrac{126653}{38}\)