1: \(78+22+18\)

\(=\left(78+22\right)+18\)

=100+18

=118

2: \(94+563+\left(106-563\right)-\left(-70\right)\)

\(=94+563+106-563+70\)

\(=\left(94+106\right)-\left(563-563\right)+70\)

=100-0+70

=170

3: \(25\cdot154-25+47\cdot25\)

\(=25\left(154-1+47\right)\)

\(=25\cdot200=5000\)

4: \(\left[5^{29}+5^{30}\left(16-11\right)\right]:5^{29}\)

\(=\left(5^{29}+5^{30}\cdot5\right):5^{29}\)

\(=\dfrac{5^{29}\cdot1+5^{29}\cdot5^2}{5^{29}}\)

\(=1+5^2=26\)

8: \(25\cdot2^3-\left(9-14\right)+\left(29-34+20\right)\)

\(=25\cdot8-\left(-5\right)+\left(-5\right)+20\)

\(=200+5-5+20\)

=220

17/21>17/29>15/29 (tự KL) b)(chép đề) B= (20+21)/(21+22)=41/43<1 (chép đề sai). Xét A= 20/21+21/22=1-1/21+1-1/22=1+1-(1/21+1/22). Ta thấy (1/21+1/22)<1 nên 1-(1/21+1/22)>0

17/21>17/29>15/29 (tự KL)
b)(chép đề)
B= (20+21)/(21+22)=41/43<1 (chép đề sai).
Xét A= 20/21+21/22=1-1/21+1-1/22=1+1-(1/21+1/22). 
Ta thấy (1/21+1/22)<1 
nên 1-(1/21+1/22)>0
Vậy 1+1-(1/21+1/22)>1+0>1
Vậy A>B

dễ quá nhưng....đang bạn

thế sao ko trả lời

f = 8 + 15 + 22 + 29

f = 23 + 22 + 29

f = 45 + 29

f = 74

f = 8 + 15 + 22 + 29

f = 74

k mik nha , mik k lại !!!!!!!!!!!!!!!!!!!!!!!!!!

=>A=(134+15) x [(134-15):7 +1]:2=149 x 18:2=1341

 Vậy A=1341

15 + 15+7+22+7+...+120+7+127+7