a,64 x 25 + 35 x 25 +25=25.(64+35+1)=25.100=2500
b) 58 x 42 + 32 x 8 + 5=2436+256+5=2697
c) A =1 +2+3+4+...+100=(100+1)x[(100-1):1+1]:2=5050
\(64\times25+35\times25+25\)
\(=25\times\left(64+35+1\right)\)
\(=25\times100\)
\(=2500\)
=25.100
= 2500
bài 2:
a,684-34.x=444
34.x=684-444
34.x=240
x=240:34=7,05
b,890:x = 35(dư8)
x=(890-15):35
x=25
1)
a) 64x25+35x25+25
=64x25+35x25+1x25
=(64+35+1)x25
=100x25
=2500
c)A=1+2+3+4+......+100
SLSH=(100-1)x1+1=100(số hạng)
A=(100+1)x100:2=5050
2)
a)684-34xX=444
34xX=684-444
34xX=240
X=240:34
X=7,05
b)890:x=35 dư 8
(890-8):x=35
882:x=35
x=882:35
x=25,2
CHÚC BẠN HỌC TỐT NHÉ!
a,64 x 25 + 35 x 25 +25=25.(64+35+1)=25.100=2500
b) 58 x 42 + 32 x 8 + 5=2436+256+5=2697
c) A =1 +2+3+4+...+100=(100+1)x[(100-1):1+1]:2=5050
Bài 1:
64*25+35*25+25=64*25+35*25+25*1=(64+35+1)*25=2500
58*42+32*8+5=