= ( 64+36)+(58+22)+(67+33)

= 100 + 80 +100

= 100x2+80

= 200+80= 280

k mk nha

64 + 58 + 36 + 67 + 33 + 32

= ( 64 + 36 ) + ( 67 + 33 ) + ( 58 + 22 )

= 100 + 100 + 80

= 200 + 80

= 280

\(a,21.\left(-15\right)+67.\left(-15\right)+\left(-15\right)+\left(-15\right).12\)

\(=21.\left(-15\right)+67.\left(-15\right)+\left(-15\right).1+\left(-15\right).12\)

\(=-15.\left(21+67+1+12\right)\)\(=-15.101=-1515\)

\(b,\left(-30\right)+76+30\)\(=\left(-30+30\right)+76=0+76=76\)

\(d,15.\left\{22-\left[400:\left(140+12.5\right)\right]\right\}\)

\(=15.\left\{22-\left[400:\left(140+60\right)\right]\right\}\)

\(=15.\left[22-\left(400:200\right)\right]\)

\(=15.\left(22-2\right)=15.20=600\)

a. (-15) x 101 = -1515 

b. (-30+30) +76 = 76

a) 67 +135 + 33 = (67 + 33) +135 = 100 +135 - 235.

b) 56 + (47 + 44) = (56+44) + 47 = 100 + 47 = 147.

c)146 +121+54 + 379 = (146 + 54) + (121+379)

= 200 + 500 = 700.

d) 27 +132 + 237 + 868 + 763 = (237 + 763) + (132 + 868) + 27

= 1000 +1000 + 27 = 2027.

e) 22 + 23 + 24 +... + 27 + 28 = (22 + 28) + (23 + 27) + (24 + 26) + 25

= 50 + 50 + 50 + 25 = 175

Sao mấy phép tính này là lớp 6 vậy??? Mấy phép tính này dễ mà!

a) 67 +135 + 33 = (67 + 33) +135 = 100 +135 - 235.

b) 56 + (47 + 44) = (56+44) + 47 = 100 + 47 = 147.

c)146 +121+54 + 379 = (146 + 54) + (121+379)

= 200 + 500 = 700.

d) 27 +132 + 237 + 868 + 763 = (237 + 763) + (132 + 868) + 27

= 1000 +1000 + 27 = 2027.

e) 22 + 23 + 24 +... + 27 + 28 = (22 + 28) + (23 + 27) + (24 + 26) + 25

= 50 + 50 + 50 + 25 = 175

Sao mấy phép tính này mà lại là lớp 6 vậy....?

troi oi coppi nhanh that day

a) 21+22+23+24+25+26+27+28

= (28+22) + (27+23) + (26+24) + (25+21)

= 50 + 50 + 50 + 46

= 196

b) 31+32+33+34+35+36+37+38+39

= (31+39) + (32+38) + (33+37) + (34+36) +35

= 70+70+70+70+35

= 315

\(=\left(-67\right).\left(-33\right)-67.77+\left(-67\right).33-77.33\)

\(=\left[\left(-67\right).\left(-33\right)+\left(-67\right).33\right]-66.77-77.33\)

\(=-77\left(66+33\right)=-77.99=-7623\)