Làm hết giúp mình nha!!! Tks nhiều

Đáp án:

Giải thích các bước giải:

Bài 1: 

a, $\frac{-2}{5}$ +0.3-$\frac{1}{25}$ 

=$\frac{-2}{5}$ +$\frac{3}{10}$ -$\frac{1}{25}$ 

=$\frac{-100}{250}$+$\frac{75}{250}$-$\frac{10}{250}$ 

=$\frac{-100+75-10}{250}$ 

=$\frac{-35}{250}$

=$\frac{-7}{50}$

b, $\frac{-7}{8}$-$\frac{5}{12}$ +1$\frac{7}{16}$

= $\frac{-42}{48}$-$\frac{20}{48}$+$\frac{69}{48}$

=$\frac{-42-20+69}{48}$

= $\frac{7}{48}$

c, 0,5+$\frac{1}{3}$+0,4+$\frac{5}{7}$+$\frac{1}{6}$-$\frac{4}{35}$

=$\frac{1}{2}$+ $\frac{1}{3}$+$\frac{2}{5}$+$\frac{5}{7}$+$\frac{1}{6}$-$\frac{4}{35}$

=$\frac{105}{210}$+$\frac{70}{210}$+$\frac{84}{210}$+$\frac{150}{210}$+$\frac{35}{210}$-$\frac{24}{210}$

=$\frac{105+70+84+35-24+150}{210}$

=$\frac{420}{210}$

=2

d, (15$\frac{1}{3}$-9$\frac{2}{7}$)-(5$\frac{1}{3}$+4$\frac{5}{7}$)

=$\frac{46}{3}$-$\frac{65}{7}$-$\frac{16}{3}$-$\frac{33}{7}$

=$\frac{46-16}{3}$-$\frac{65+33}{7}$

=$\frac{30}{3}$-$\frac{98}{7}$

=10-14

=-4

Bài 2: 

a, $\frac{-7}{5}$.$\frac{5}{8}$.$\frac{17}{-7}$.(-32)

=$\frac{-7.5.17.(-32)}{5.8.(-7)}$

=17.(-4)

=-68

b, -66.(0.5-$\frac{1}{3}$-$\frac{1}{6}$)+$\frac{1}{2}$-0,75

=-66($\frac{1}{2}$-$\frac{1}{3}$-$\frac{1}{6}$)+$\frac{1}{2}$-$\frac{3}{4}$

=-66.($\frac{3}{6}$-$\frac{2}{6}$-$\frac{1}{6}$)+$\frac{1}{2}$-$\frac{3}{4}$

=-66.$\frac{3-2-1}{6}$+$\frac{1}{2}$-$\frac{3}{4}$

=-66.0+$\frac{1}{2}$-$\frac{3}{4}$

=$\frac{1}{2}$-$\frac{3}{4}$

=$\frac{2}{4}$-$\frac{3}{4}$

=$\frac{2-3}{4}$

=$\frac{-1}{4}$

c, 2³+3.($\frac{1}{9}$)∧0-2²:4+((-3)².$\frac{1}{3}$):2

=8+3.1-4:4+(9.$\frac{1}{3}$):2

=8+3-1+3:2

=$\frac{23}{2}$

d, ($\frac{5}{31}$+$\frac{13}{45}$):$\frac{1}{4}$-($\frac{5}{31}$-$\frac{32}{45}$):$\frac{1}{4}$

=($\frac{5}{31}$+$\frac{13}{45}$).4-($\frac{5}{31}$-$\frac{32}{45}$).4

=($\frac{5}{31}$+$\frac{13}{45}$-$\frac{5}{31}$+$\frac{32}{45}$).4

=$\frac{32+13}{45}$.4

=$\frac{45}{45}$.4

=1.4

=4

#Muoi