Viết số thích hợp vào ô trống:

Số lớn	Số bé	Số lớn gấp mấy lần số bé?
21	7
40	8
24	4
10	5
54	6

a) 450 – (25 – 10) = ....................

                              = ....................

450 – 25 – 10 = ...........................

  = ............................

c) 410 – (50 + 30) = ....................

                              = ....................

410 – 50 + 30 = ...........................

                       = ...........................

b) 36 : 6 : 2 = .........................

                    = .........................

36 : (6 : 2) = ...........................

                  = ...........................

d) 11 × 6 : 3 = ........................

                     = .......................

11 × (6 : 3) = .........................

                   = .........................

a) 417 – (37 – 20) = ..........................

= ..........................

c) 248 : (4 : 2) = ..........................

   = ..........................

b) 826 – (70 + 30) = ..........................

= ..........................

d) (300 + 100) × 2 = ..........................

= ..........................

a) 1 000 – (223 + 737)

= .................................

= .................................

b) (428 + 139) : 7

= ................................

= ................................

c) (236 – 128) × 9

= ...............................

= ...............................