Question

Làm hộ

Answer 1

Chỉ làm bài tập 2 na mã thôi ko cần làm câu hỏi nha

Answer 2

a,=\(\dfrac{-4}{9}\).(\(\dfrac{7}{15}\)+\(\dfrac{8}{15}\))

=\(\dfrac{-4}{9}\).1

=\(\dfrac{-4}{9}\)

b,=\(\dfrac{-5}{4}\).\(\dfrac{16}{25}\)+\(\dfrac{-5}{4}\).\(\dfrac{9}{25}\)

=\(\dfrac{-5}{4}\).(\(\dfrac{16}{25}\)+\(\dfrac{9}{25}\))

=\(\dfrac{-5}{4}\).1

=\(\dfrac{-5}{4}\)

c,=(\(4\dfrac{11}{23}\)+\(2\dfrac{12}{23}\))-(\(\dfrac{9}{14}\)+\(\dfrac{5}{4}\))

=7-\(\dfrac{53}{28}\)

=\(\dfrac{143}{28}\)

Answer 3

d,=(\(2\dfrac{13}{27}+3\dfrac{14}{27}\))-(\(\dfrac{7}{15}\)+\(\dfrac{8}{15}\))

=6-1

=5

e,=\(11\dfrac{1}{4}-5\dfrac{1}{4}-2\dfrac{5}{7}\)

=6\(-2\dfrac{5}{7}\)

=\(3\dfrac{2}{7}\)

f,=\(\dfrac{7}{19}.\left(\dfrac{8}{11}+\dfrac{3}{11}\right)+\dfrac{12}{19}\)

=\(\dfrac{7}{19}.1+\dfrac{12}{19}\)

=\(\dfrac{7}{19}+\dfrac{12}{19}\)

=1

Answer 4

Bài 2: 

a) -4/9.7/15+4/-9.8/15 = -4/9.(7/15+8/15) = -4/9.1 = -4/9

b) 5/-4.16/25+-5/4.+9/25 = -5/4.(16/25+9/25) = -5/4.1 = -5/4

c) 4/11/23-9/14+2/12/23-5/4 = 103/23+58/23-9/14-5/4 = 7-1 = 6

d) 2/13/27-7/15+3/14/27-8/15 = 67/27+95/27-7/15-8/15 = 6-1 = 5

e) 11/1/4-(2/5/7+5/1/4) = 45/4-19/7-21/4= 45/4-21/4-19/7 = 6-19/7 = 23/7

g) 7/19.8/11+7/19.3/11+12/19 = 7/19.(8/11+3/11)+12/19 = 7/19+12/19 = 1