Question

Tính nhanh:
a. 8,51 + 99 x 8,51

b. ​0,25 x 3,78 x 400

Answer 1

a. 8,51 + 99 x 8,51

= 8,51 + 99 x 8,51 + 1

= 8,51 x ( 99 + 1 ) 

= 8,51 x 100 

= 851

b) 0,25 x 3,78 x 400

= ( 0,25 x 400 ) x 3,78

= 100 x 3,78 

= 378

Answer 2

A.8,51+99×8,51= =8,51+99×8,51×1 =8,51×(99+1) =8,51×100 =851 B.0,25×3,78×400= =(0,25×400)×3,78 =100×3,78 =378

Answer 3

Trl:

a) 8,51 + 99 x 8,51

= 8,51 + 99 x 8,51 + 1

= 8,51 x ( 99 + 1 )

= 8,51 x 100

= 851

b) 0,25 x 3,78 x 400

= (0,25 x 400) x 3,78

= 100 x 3,78

= 378

Hc tốt

Answer 4

a, 8 , 51 + 99 . 8, 51 

= 8,51 . ( 1 + 99 ) 

= 8,51 . 100 

= 851 

b, 0,25 . 3,78 . 400 

= ( 0, 25 . 400 ) . 3,78 

= 100 . 3,78 

= 378