Tính nhanh:
a) 50+50+50+50+50+50+50+50+50+50+50+50=?
b) 100+100+100+100+100+100+100+100+100=?
50 + 50 + 90 + 10 + 100 + 100 =?
50-50-50+100-90+58-60=?
50+50=100
50+60=?
x + 50 = 100 + 50
100 + 50 + 50 + 1 =??
x : 50 = 100 + 50
x : 50 = 100 + 50
Tính nhẩm:
100 – 50 =
950 – 50 =
515 – 415 =
100 + 100 : 4 - 50 : 2