Question

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Hãy rút gọn phân số

a) 1919 / 2121

b) 17 x 5 - 17 / 120 - 103

c) 2929 - 101 / 2x 1919 + 404

Answer 1

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

= \(\dfrac{10200}{120}\) - \(\dfrac{17}{120}\) - \(\dfrac{12360}{120}\)

= \(\dfrac{10183}{120}\) - \(\dfrac{12360}{120}\)

= \(\dfrac{-2177}{120}\)

 

Answer 2

c; 2929 - \(\dfrac{101}{2\times1919}\) + 404

= 2929 - \(\dfrac{1}{38}\) + 404

= \(\dfrac{111302}{38}\) - \(\dfrac{1}{38}\) + \(\dfrac{15352}{38}\)

= \(\dfrac{111301}{38}\) + \(\dfrac{15352}{38}\)

 = \(\dfrac{126653}{38}\)