57 x 9
= 57 x (10-1)
= 57 x 10 - 57
= 570 - 57
= 513.
62 x 49
= 62 x ( 50-1)
= 62 x 50 - 62
=3 100 - 62
=3 038.
753 x 99
= 753 x ( 100-1)
= 753 x 100 - 753
= 75 300 - 753
= 74 547.
53 x 29
= 53 x ( 30-1)
= 53 x 30 - 53
= 1 590 - 53
=1 537.
a 57x9
=57x(10-1)
=57x10-57x1
=570-57
=113
b 62x49
=62x(50-1)
=62x50-62x1
=3100-62
=3038
c 54x99
=53x(100-1)
=53x100-53x1
=5300-53
=5247
d 53x29
=53x(30-1)
=53x30-53x1
=1537
a)57x9 b)62x49
=57x(10-1) =62x(50-1)
=570-57 =3100-62
=513 =3038
c)753x99 d)53x29
=753x(100-1) =53x(30-1)
=75300-753 =1590-53
=74547 =1537
k mình nha bạn
a ) 57 x 9 = 57 x (10 - 1) = 57 x 100 - 57 x1 = 5700 - 57 = 5643
b ) 62 x 49 = 62 x ( 50 - 1) = 62 x 50 - 62 x1 = 3100 - 62 = 3038
753 x 99 = 753 x (100-1) = 753x100-753x1 = 75300 - 753 =74547
53 x 29 = 53 x (30-1) = 53x 30 - 53 x 1 = 1590 - 53 = 1537
K tớ nhé
a,
57 x 9
= 57 x (10 - 1)
= 57 x 10 - 57 x 1
= 570 - 57
= 513
b,
62 x 49
= 62 x (50 - 1)
= 62 x 50 - 62 x 1
= 3100 - 62
= 3038
c,
753 x 99
= 753 x (100 - 1)
= 753 x 100 - 753 x 1
= 75300 - 753
= 74547
d,
53 x 29
= 53 x (30 - 1)
= 53 x 30 - 53 x 1
= 1590 - 53
= 1537
