66\(\times\)50=3300
72\(\times\)125=9000
38\(\times\)5=190
2000\(\div\)=80
7300\(\div\)50=146
4970\(\div\)5=994
81000\(\div\)648
Học tốt!
Tính nhẩm
a) 66.50 = 3300
b) 72.125 = 9000
c) 38.5 = 190
d) 2000:25 = 80
e) 7300:50 = 146
g) 4970:5 = 994
h) 81000:125 = 648
a) 66.50=3300
b) 72.125=9000
c) 38.5=190
d) 2000:25=80
e) 7300:50=146
g) 4970:5=994
h) 81000:125=648
Tính nhẩm
a) 66.50=(60+6).50=60.50+6.50=3000+300=3300
b) 72.125=8.9.125=1000.9=9000
c) 38.5=(30+8).5=30.5+8.5=150+40=190
d) 2000:25=20.100:25=20.4=80
e) 7300:50=(7000+300):50=7000:50+300:50=140+6=146
g) 4970:5=(4000+900+70):5=4000:5+900:5+70:5=800+180+14=994
h) 81000:125=(80000+1000):125=80000:125+1000:125=640+8=648
9966\(\times\)50=33\(\times\)2\(\times\)50=33\(\times\)100=3300
72\(\times\)125=7,2\(\times\)10\(\times\)125=10\(\times\)900=9000
38\(\times\)5=19\(\times\)2\(\times\)5=19\(\times\)10=190
2000\(\div\)25=2000\(\div\)5\(\div\)5=400\(\div\)5=80
7300\(\div\)50=7300\(\div\)5\(\div\)10=1460\(\div\)10=146
4970\(\div\)5=497\(\times\)(10\(\div\)5)=497\(\times\)=994
81000\(\div\)125=81000\(\div5\div5\div5=16200\div5\div5=3240\div5=648\)