\(20-[30-(5-1)\)2\(]\)
= \(20-[30-(4)\)2\(]\)
= \(20 -[30-16]\)
= \(20 -14\)
= \(6\)
\(20-[30-(5-1)\)2\(]\)
= \(20-[30-(4)\)2\(]\)
= \(20 -[30-16]\)
= \(20 -14\)
= \(6\)
1 phút 20 giây + 1 phút 30 giây =
2 phút 30 giây + 1 phút 20 giây=
2 giờ 20 phút * 5 giờ 20 phút =
các bn có được tặng quà 8-3 ko
a) N = 1/2 + 1/6+ 1/12 + 1/20 + 1/30 +1/42 + 1/56 + 1/72 +1/90
b) 5/8 + 2/9 -2/5 + 3/8 + 4/9 + 1/3 - 3/5 =
c) 4 1/5 + 5 1/3 - 2 2/3 x 3 1/5 + 9/25 : 9/20 =
TÍNH NHANH
1/2 + 5/6 + 11/12 + 19/20 + 29/30
(2017 - 1/4-2/5-3/5-4/7-...-2017/2020):(1/20+1/25+1/30+1/35+....+1/10100)
1) 1/2 + 5/6 + 11/12 + 19/20 + 29/30 + 41/42 + 55/56
(2017--1/4-2/5-3/6-....-2017/2020):(1/20+1/25+1/30+1/35+.........+1/10100)
a=1+2+3+4+5+...+1000
b=5+10+15+20+...+5000
c=10+20+30+...+10000
d=20+40+60+...+20000
tìm a,b,c,d
b= ( 2017 - 1/4 - 2/5 - 3/6 - ... - 2017/2020) : ( 1/20+1/25+1/30 +1/35 + ... +1/10100)
1/2+5/6+11/12+19/20+24/30+41/42+55/56
a.1/2+5/6+11/12+19/20+29/30+41/42+55/56