Question

[friend forever II Lê Tiến Đạt]

tính bằng cách thuận tiện nhất 

a) (125*36) : (5*9)

b) 6/16+8/18+10/16+10/18

c)5,6*2 +2,8*8+11,2*2-48,5

Answer 1

[nguyenthithanhphuong]

1. b) (6/16+10/16)+(8/18+10/18)=16/16+18/18=1+1=2

Answer 2

[Tạ Giang Thùy Loan]

a,(125*36):(5*9)=(125x40-125*4):45=(5000-500):45=4500:45=100

b,\(\frac{6}{16}+\frac{8}{18}+\frac{10}{16}+\frac{10}{18}\)\(=\left(\frac{6}{16}+\frac{10}{16}\right)+\left(\frac{8}{18}+\frac{10}{18}\right)\)\(=\frac{16}{16}+\frac{18}{18}=1+1=2\)

c,5,6*2+2,8*8+11,2*2-48,5=5,6*2+2,8*2*4+5,6*2*2-48,5=5,6*2+5,6*4+5,6*4-48,5

=5,6*(2+4+4)-48,5=5,6x10-48,4=56-48,5=7,5