[88 :  8]   x 12 = 132

( 88 x 12 ) : 8 = ( 88 : 8 ) x 12

                      = 11 x 12

                      = 132

Hướng dẫn giải:

a) 513 x 4 + 513 x 6

= 513 x (4 + 6)

= 513 x 10 = 5130

b) 88 x 9 – 88 x 8

= 88 x (9 – 8)

= 88 x 1 = 88

a) 513 x 4 + 513 x 6 = 513 x (4 + 6)
                                 = 513 x 10
                                 = 5 130

b) 88 x 9 - 88 x 8 = 88 x (9 - 8)
                            = 88 x 1
                            =88

24 x 55 + 12 x 88 + 24

= ( 24 x 55 ) + ( 12 x 88 ) + 24

= 1320 + 1056 + 24

= 2376 + 24

= 2400

_HT_

\(24\cdot55+12\cdot88+24\)

\(\Leftrightarrow\left(24\cdot55\right)+\left(24\cdot88:2\right)+24\)

\(\Rightarrow\left(24+55\right)+\left(24\cdot44\right)+24\)

\(\Leftrightarrow24\left(55+44+1\right)\)

\(\Leftrightarrow24\cdot100\)

\(\Leftrightarrow2400\)

Hướng dẫn giải:

a. 88 + 75 + 12 = (88 + 12) + 75 = 100 + 75 = 175

b. 146 + 55 + 54 = (146 + 54) + 55 = 200 + 55 = 255.

 o0                                                   rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr                           ẻu

=(12+88) +(34+46)*2+(55+65)=100+2*80+120=100+160+120=380

kết quả là 380

12 + 34 + 88 + 46 + 55 + 34 + 65 + 46

= (12 + 88) + (34 + 46) + ( 55 + 65) + ( 34 + 46)
= 100 + 80 + 120 + 80

= 380

88-8+8........+8(11Số)

88-(8*11)

88-88

=0

88-8+8+8+...8(11 số 8)

=88-(8*11)

=88-88

=0

Tính nhanh 28,2 x( 12 + 88)=  28,2 x 100

Hướng dẫn giải:

a) 280 x 71 : 14 = (280 : 14) x 71 = 20 x 71 = 1420

b) 125 x 88 : 11 = 125 x (88 : 11) = 125 x 8 = 1000

\(\dfrac{3}{12}\)x\(\dfrac{15}{6}\)x\(\dfrac{8}{5}\)

=> \(\dfrac{5}{8}\)x\(\dfrac{8}{5}\)

=>1

\(\dfrac{3}{12}\times\dfrac{15}{6}\times\dfrac{8}{5}=1\)

=1