Question

Va rog sa ma ajutati cu 3 si 5​

Answer 1

3.

6/7 x 21/8 = 6 x 21/7 x 8 = 126/56 = 18/8 = 9/4 (2 1/4)

2 8/9 : 13/6 = 26/9 : 13/6 = 26 x 6/9 x 13 (reducem 26 cu 13) = 2 x 6/9 x 1 = 12/9

(1 1/3) [1,(3)]

5.

16/20 + 15/20 = 31/20 sau 16/20 + 15/20 (impartim la 2 fractiile) = 8/10 + 7.5/10 = 0.8 + 0.75 = 1.55 (nu stiu despre ce "a doua metoda" merge vorba aici)

I. 4/9 x (3/7 + 5/4) = 4/9 x 3/7 + 4/9 x 5/4 = 12/63 + 20/36 (inmultim prima fractie la 4 si a doua la 7)= 48/252 + 140/252 = 188/252 (impartim fractia la 4)  = 47/63

II. 4/9 x (3/7 + 5/4) (rezolvam mai intai ce e in paranteza prin inmultirea la 3/7 cu 4 si 5/4 cu 7) = 4/9 x (12/28 + 35/28) = 4/9 x (47/28) = 4 x 47/9 x 28 = 188/252 = 47/63