tính nhanh:
23 +67 +24 +09 +67=
87 +98 +76 +32=
87 +43 +98 +12=
giaỉ ra nha
tính nhanh: 23 +67 +24 +09 +67= 87 +98 +76 +32= 87 +43 +98 +12= giaỉ ra nha
By Margaret
By Margaret
tính nhanh:
23 +67 +24 +09 +67=
87 +98 +76 +32=
87 +43 +98 +12=
giaỉ ra nha
$23+67+24+9+67=(23+67)+(24+9+67)=90+100=190$
$87+98+76+32=(98+32)+87+76=130+87+76=130+163=293$
$87+43+98+12=(87+43)+(98+12)=130+110=240$
Đáp án:
23+67+24+9+67=(67+23)+(24+67+9)
=90+100=190
87+98+76+32=(32+98)+(76+87)
=130+163
=293
87+43+98+12=(87+43)+(98+12)
=130+110
=240