câu c)-2002

bạn sửa cho mình nhé

2Tính nhanh:

a) 152. 19 + 152. 81                                    b) 197. 50 – 50. 98 + 50

=152.(19+81)                                                =50.(197-98)+50                                          

=152.100                                                       =50.99+50

=1520                                                             =5000

b) 1000 + (–470 ) + 3215 +(–530)                   c) – 479 – ( 2002 – 479 ) 

=1000+[ (–470 )+ (–530) ]+ 3215               =-479+2002+479

=1000+(-1000)+3215                                =(-479+479)+2002

=0+3215                                                    =0+2002

=3215                                                        =2002

dấu ^ là dấu mũ

5²⁰ : (5¹⁵.15 + 5¹⁵.10)

=5^20 :[5^15.(15+10)]

=5^20 :[5^15.25]

=5^20 :5^17

=5^3

=125

dấu ^ này là dấu mũ

Câu 3:

a)(6-10)+150                  75.95-75.45

=(-4)+150                      =75.(95-45)

=146                              =75.50

                                      =3750

B)45-4x=37                    (3x-6).3=3^4

4x =45-37                      (3x-6)=3^4:3

4x =8                              (3x-6)=27

X=8:4                             3x =27+6

X=2                               3x =33

                                      x=33:3

                                      x=11

Đáp án là A