-1/2 + -7/24 + 19/24

=-19/24 + 19/24 =0

-1/2 + -7/24 + 19/24

=-12/24 + -7/24 + 19/24

=-19/24 + 19/24

=0

Học sinh nhẩm và ghi kết quả như sau:

35 : 5 = 7

28 : 7 = 4

24 : 6 = 4

21 : 3 = 7

35 : 7 = 5

28 : 4 = 7

24 : 4 = 6

21 : 7 = 3

35 : 5 = 7

28 : 7 = 4

24 : 6 = 4

21 : 3 = 7

35 : 7 = 5

28 : 4 = 7

24 : 4 = 6

21 : 7 = 3

-24 ( - 3 - 7 ) -  7 (-24 -3 ) = 429

=429 nha bn

\(\dfrac{7}{5}\times\dfrac{11}{24}\times\dfrac{5}{7}\times\dfrac{24}{55}\\ =\left(\dfrac{7}{5}\times\dfrac{5}{7}\right)\times\left(\dfrac{11}{24}\times\dfrac{24}{55}\right)\\ =1\times\dfrac{1}{5}\\ =\dfrac{1}{5}\)

\(\dfrac{7x11x5x24}{5x24x7x55}\)=\(\dfrac{11}{55}\)=\(\dfrac{1}{5}\)

a) \(\dfrac{17}{24}\times\dfrac{3}{51}=\dfrac{51}{1224}=\dfrac{1}{24}\)

b) \(\dfrac{6}{7}\div\dfrac{24}{49}-\dfrac{1}{24}\)

\(=\dfrac{7}{4}-\dfrac{1}{24}=\dfrac{41}{24}\)

a) \(\dfrac{17}{24}\)x\(\dfrac{3}{51}=\dfrac{51}{1224}=\dfrac{1}{24}\)

b) \(\dfrac{6}{7}:\dfrac{24}{49}-\dfrac{1}{24}=\dfrac{7}{4}-\dfrac{1}{24}=\dfrac{41}{24}\)

a) 56 giờ 24 phút

b) 1 phút 12 giây

a, = 15 x (3+7) + 15 = 15 x 10 + 15 = 150 + 15 = 165

b, = 24 x 18 - 24 x 8 + 24 = 24 x (18-8) + 24 = 24 x 10 + 24 = 240 + 24 = 264

k mk nha

a,15*3+15*7+15

=15*(3+7)

=15*10

=150

b,24*18-24*7

=24*(18-7)

=24*11

=264

tk cho mk nha^-^

\(\frac{2}{7}:\frac{13}{24}+\frac{2}{7}:\frac{5}{24}\)

\(=\frac{2}{7}x\frac{24}{13}+\frac{2}{7}x\frac{14}{5}=\frac{2}{13}x\frac{24}{7}+\frac{2}{5}x\frac{24}{7}\)

\(=\frac{24}{7}x\left(\frac{2}{13}+\frac{2}{5}\right)=\frac{24}{7}x\frac{36}{65}=\frac{864}{455}\)

=48/91+48/35

=864/455

   study well

  k nha

  mk xin cảm ơn mọi người

569/232 bạn nhé mình chắc 100%

\(G=\dfrac{7}{8}+\dfrac{11}{24}+\dfrac{5}{8}+\dfrac{23}{24}+\dfrac{11}{8}+\dfrac{13}{24}\\ \Rightarrow G=\left(\dfrac{7}{8}+\dfrac{5}{8}+\dfrac{11}{8}\right)+\left(\dfrac{11}{24}+\dfrac{23}{24}+\dfrac{13}{24}\right)\\ \Rightarrow G=\dfrac{23}{8}+\dfrac{47}{24}\\ \Rightarrow G=\dfrac{69}{24}+\dfrac{47}{24}\\ \Rightarrow G=\dfrac{116}{24}\\ \Rightarrow G=\dfrac{29}{6}\)

hay quá mà mik còn quá nhiều