Question

tinh nhanh 2.75*21+4*25-7*2.75

 

Answer 1

= 2.75*(21-7) + 4*25

= 2.75*14 + 4*25

= 2.75*(10+4) + 4*25

Answer 2

Ta có 2,75*21+4*25-7*2,7

=2,75*(21-7)+4*25

=2,75*14+100

=38,5+100

=138,5

Answer 3

2.75*(21-7)+4*25

2.75*14+4*25

38.5 + 100

138.5