a) (-124) + 24 = -100
b) 37. 78 + 37. 22
=  37 . ( 78 + 22 )
=  37 . 100
= 3700

\(a) (-124) + 24 = -100 b) 37. 78 + 37. 22 = 37 . ( 78 + 22 ) = 37 . 100 = 3700\)

a) (- 124) + 24                                          b) 37 . 78 + 37 . 22

= - ( 124 - 24)                                              =37 . ( 78 + 22)

= - 100                                                        =37 . 100 

                                                                    3700

\(=64\cdot\dfrac{-1}{8}+100\cdot\dfrac{1}{100}\)

=-8+1

=-7

\(A=-\dfrac{1}{6}-\left[\dfrac{9}{16}-\dfrac{9}{8}+\dfrac{3}{4}\right]\)

\(=\dfrac{-1}{6}-\dfrac{9-18+12}{16}=\dfrac{-1}{6}-\dfrac{3}{16}\)

\(=\dfrac{-8}{48}-\dfrac{9}{48}=-\dfrac{17}{48}\)

\(B=\left(-\dfrac{3}{4}+\dfrac{3}{4}\right)^2+\dfrac{3}{4}\cdot\dfrac{-5}{9}+7^3\)

=-15/36+343

=343-5/12=4111/12

\(\dfrac{\dfrac{5}{3}-\dfrac{5}{7}+\dfrac{5}{9}}{\dfrac{10}{3}-\dfrac{10}{7}+\dfrac{10}{9}}=\dfrac{5\left(\dfrac{1}{3}-\dfrac{1}{7}+\dfrac{1}{9}\right)}{10\left(\dfrac{1}{3}-\dfrac{1}{7}+\dfrac{1}{9}\right)}=\dfrac{1}{2}\)

e: =5/7(5/11+2/11-14/11)

=5/7(-7/11)=-5/11

f: =-5/4(2/11+9/11)+1+3/4

=-5/4+7/4

=2/4=1/2

g: =-5/7(3/13+10/13)+1+5/7

=-5/7+1+5/7

=1

h: =7/4(29/5-9/5)+41/13

=-7+41/13=-50/13

Kết quả là 7/20 nhé bạn!!!

Chúc bạn học tốt

Đáp án cần chọn là: D

Ta có: (90.121+8.121):49=121.(90+8):49=121.98:49=11858:49=242