Tính nhanh: a, 81×99+81 b, 2021×11-2021 c,47,54+47,27+47×19 d, 69+69×99 12/08/2021 Bởi Ayla Tính nhanh: a, 81×99+81 b, 2021×11-2021 c,47,54+47,27+47×19 d, 69+69×99
a, 81×99+81 =81 x(99+1) = 8100 b) 2021 . 11 – 2021= 2021 . 11 – 2021 . 1= 2021 . (11 – 1)= 2021 . 10= 20210 c) 47 . 54 + 47 . 27 + 47 . 19 = 47 . (54 + 27 + 19) = 47 . 100 = 4700 d) 69 + 69 . 99 = 69 . 1 + 69 . 99 = 69 . (99 + 1) = 69 . 100 = 6900 Hidden ninja Bình luận
a) 81 . 99 + 81 = 81 . 99 + 81 . 1 = 81 . (99 + 1) = 81 . 100 = 8100 b) 2021 . 11 – 2021 = 2021 . 11 – 2021 . 1 = 2021 . (11 – 1) = 2021 . 10 = 20210 c) 47 . 54 + 47 . 27 + 47 . 19 = 47 . (54 + 27 + 19) = 47 . 100 = 4700 d) 69 + 69 . 99 = 69 . 1 + 69 . 99 = 69 . (99 + 1) = 69 . 100 = 6900 Chúc học tốt!!! Bình luận
a, 81×99+81
=81 x(99+1)
= 8100
b) 2021 . 11 – 2021
= 2021 . 11 – 2021 . 1
= 2021 . (11 – 1)
= 2021 . 10
= 20210
c) 47 . 54 + 47 . 27 + 47 . 19
= 47 . (54 + 27 + 19)
= 47 . 100
= 4700
d) 69 + 69 . 99
= 69 . 1 + 69 . 99
= 69 . (99 + 1)
= 69 . 100
= 6900
Hidden ninja
a) 81 . 99 + 81
= 81 . 99 + 81 . 1
= 81 . (99 + 1)
= 81 . 100
= 8100
b) 2021 . 11 – 2021
= 2021 . 11 – 2021 . 1
= 2021 . (11 – 1)
= 2021 . 10
= 20210
c) 47 . 54 + 47 . 27 + 47 . 19
= 47 . (54 + 27 + 19)
= 47 . 100
= 4700
d) 69 + 69 . 99
= 69 . 1 + 69 . 99
= 69 . (99 + 1)
= 69 . 100
= 6900
Chúc học tốt!!!