142 x 12+ 142 x 18 = ( 12 + 18) x 142 = 30 x 142 = 4260
49 x 365 - 39 x 365 = ( 49 - 39) x 365 = 10 x 365 = 3650
4 x 18 x 25= ( 4 x 25) x 18 = 100 x 18 = 1800
Tính bằng cách thuận tiện nhất
142 x 12+ 142 x 18
=142 x (12+18)=142 x 30=4260
49 x 365 - 39 x 365
(49-39) x 365=10 x 365=3650
4 x 18 x 25
=(4 x 25) x 18=100 x 18=1800
\(142 . ( 12 + 18 )\)
=\(142.30\)
=\(4260\)
(49 - 39) . 365
10 . 365
3650
(25 x 4)x18
100x18
1800
142 x 12+ 142 x 18
= 142 x (12 + 18)
= 142 x 30
= 4260
49 x 365 - 39 x 365
= 365 x (49 - 39)
= 365 x 10
= 3650
4 x 18 x 25
= 4 x 25 x 18
= 100 x 18
= 1800
142 x 12+ 142 x 18
= 142 x ( 12+18)
= 142 x 20
= 2840
49 x 365 - 39 x 365
= 365 x ( 49-39)
= 365 x 10
= 3650
4 x 18 x 25
= 18 x (25 x 4)
= 18 x 100
= 1800
Tính bằng cách thuận tiện nhất:
\(142\times12+142\times18\)
\(=142\times\left(12+18\right)\)
\(=142\times30\)
\(=4260\)
\(49\times365-39\times365\)
\(=365\times\left(49-39\right)\)
\(=365\times10\)
\(=3650\)
\(4\times18\times25\)
\(=\left(4\times25\right)\times18\)
\(=100\times18\)
\(=1800\)