Register Now

Login

Lost Password

Lost your password? Please enter your email address. You will receive a link and will create a new password via email.

222-9+11+12:2*14+14 = ? ( )

Toán Lớp 6: Tính bằng cách hợp lí nhất: a) −2021 + (−22 + 87 + 2021) b) 1152 − (374 + 1152) + (−65 + 374) c) 942 − 2567 + 2563 − 1942 d) −263 + 197

Toán Lớp 6: Tính bằng cách hợp lí nhất:
a) −2021 + (−22 + 87 + 2021)
b) 1152 − (374 + 1152) + (−65 + 374)
c) 942 − 2567 + 2563 − 1942
d) −263 + 1975 + (−737) + (−905)

Comments ( 2 )

  1. Lời giải và giải thích chi tiết:
    a)
    -2021 + (-22 + 87 + 2021)
    = (-2021) + 2021 + (-22) + 87
    = (-22) + 87
    = 65
    b)
    1152 – (374 + 1152) + (-65 + 374)
    = 1152 – 374 – 1152 – 65 + 374
    = (1152 – 1152) – (374 – 374) – 65
    = 0 – 0 – 65
    = -65
    c)
    942 – 2567 + 2563 – 1942
    = (942 – 1942) – (2567 – 2563)
    = (-1000) – 4
    = -1004
    d)
    -263 + 1975 + (-737) + (-905)
    = [(-263) + (-737)] + (1975 – 905)
    = (-1000) + 1070
    = 70

  2. a) −2021 + (−22 + 87 + 2021)
    = -2021 +2021 +( -22+87)
    = 0 + 65 
    = 65
    b) 1152 − (374 + 1152) + (−65 + 374)
    = 1152 -374 -1152 -65+374
    = 1152-1152 -374+374-65
    = 0 +0 -65
    – -65
    c) 942 − 2567 + 2563 − 1942
    = 942 -1942 -2567+2563
    =  -1000 -4
    = -1004
    d) −263 + 1975 + (−737) + (−905)
     = -263+1975-737-905
    = -263-737+1975-905
    = – 1000 +1070
    = +70

Leave a reply

222-9+11+12:2*14+14 = ? ( )