Question

Por favor alguma resposta nao consigo fazer

Answer 1

Resposta:

Explicação passo a passo:

Para multiplicação de frações, temos:

$\frac{a}{b} . \frac{c}{d} = \frac{a.c}{b.d}$

20.
a) 3/5 . 7/4 = 21/20
b) 4/7 . 2/3 = 8/21
c) 1/3 . 9/2 = 9/6 = 3/2
d) 18/9 . 3/6 = 54/54 = 1
e) 4/7 . 10/3 . 1/3 = = 40/63
f) 1/5 . 3/2 . 25/9 = 75/90
g) 4/9 . 6/5 . 15/12 . 3
h) 4 . 9/16 . 4/3 . 2/3 . (1 1/2) = 288/144 . (3/2) = 2 . (3/2) = 6/2 = 3
i) 2 3/8 . 16/57 . (1 1/2) = 19/8 . 16/57 . (3/2) = 912/912 = 1

21. 3/4 de 2/3 = 3/4 . 2/3 = 6/12 = 1/2

22. (2 4/5) . (3 4/7) = (14/5) . (25/7) = 350/35 = 10
10 - (6 2/3) = 10 - 20/3 = 10/3 = 3,33...

Sim, 10/3, igual a 3,33.. é maior que 3.

23.
A) 5/15 . (7/10 - 1/5) = 5/15 . (7-2/10) = 5/15 . 5/10 = 25/150 = 1/6
B) 12/9 . (2/3 + 5/6) = 12/9 . ( 4 + 5/6) = 12/9 . 9/6 = 108/54 = 2
C) (1/2 + 3/4) . (1 + 1/15) = (2+3/4) . (16/15) = (5/4) . (16/15) = 80/60 = 4/3
D) 6.15/36 + (2 2/3) . (2 1/4) = 90/36 + (8/3) . (9/4) = 90/36 + 72/12 = 45/18 + 6 = 153/18 = 51/6 = 17/2