a) 5+8+11+14+...+38+41.(13 số hạng )

=(5+41)+(8+38)+(11+35)...+(20+26)+23(6 cặp )

=46+46+46+...+46+23

=46x6+23=276+23=299

b)5219+6998

=12217

c)4996+2314+1003

=(4996+2314)+1003

=7310+1003=8313

8313 click cho nhé

4996+2314+1003=8313

4996 + 2314 + 1003

= ( 4996 + 2314 ) + 1003

= 7310 + 1003

= 8313

4996+2314+1003=8313

Chúc bạn chăm ngoan học giỏi ,vâng lời ông bà , cha mẹ!!!.Kết bạn với mình nha!!!!!!!!!!!

4996 : 24 = 1249/6

Hay ≈ 210

Ko chia hết nha

ok bạn

4996 : 7 = 713,7

K nha

a ) 2 1 4 : 3 5 4 = 9 4 : 17 4 = 9 4 . 4 17 = 9 17

b ) − 3 1 7 : − 2 3 14 = − 22 7 : − 31 7 = 22 31

=  225.55 +  225.55

=  451.1 

a)\(65.3,47+3,47.65\)
\(=65.\left(3,47+3,47\right)\)
\(=65.6,94\)
\(=451,1\)

\(65\times\left(3,47+3,47\right)=65\times6,94=451,1\)

a: \(78\cdot82=80^2-4=6400-4=6396\)

b: \(45^2+90\cdot55+55^2=100^2=10000\)

`30 xx 25 xx 7 xx8`

`=(30 xx7) xx (25xx8)`

`=210 xx200`

`=42000`

`----`

`75 xx 8 xx 12 xx 14`

`=(75xx8) xx(12xx14)`

`=600xx168`

`=100800`

\(a.30\times25\times7\times8=\left(30\times7\right)\times\left(25\times8\right)=210\times200=42000\)

\(b.75\times8\times12\times14=\left(75\times12\right)\times\left(8\times14\right)=900\times112=100800\)

\(a,30.25.7.8\\ =\left(30.7\right).\left(25.8\right)\\ =210.200\\ =42000\\ b,75.8.12.14\\ =\left(75.12\right).\left(8.14\right)\\ =900.112\\ =100800\)

=8,95*90+89,5

=89,5(9+1)

=895