Question

Tính nhanh: 

a. 2006*125+1000

   731-47+69-253

b.3,54*73+0,46*25+3,54*26+0,46*75+3,54

Answer 1

a)2006x125+1000=250,75x125x8+1000=250,75x1000+1000=1000(250,75+1)=1000x251,75=251750

731-47+69-253=(731+69)-(47+253)=800-300=500

b)3,54x73+0,46x25+3,54x26+0,46x75+3,54

=3,54(73+26+1)+0,46(25+75)

=3,54x100+0,46x100

=354+46=400