Question

tính nhanh

0,78 x 50 +  0,39 x  22 x  2 + 3 x 28 x0,26

lam giup mk voi 

lam ca bai ,ghi day du

Answer 1

Ta có:\(0,78\times50+0,39\times22\times2+3\times28\times0,26\)

\(=0,78\times50+0,78\times22+0,78\times28\)

\(=\left(50+22+28\right)\times0,78\)

\(=100\times0,78\)

\(=78\)

Answer 2

=39+0,39x22x2+3x28x0,26

=39+8,58x2+3x28x0,26

=39+17,16+3x28x0,26

=39+17,16+84x0,26

=39+17,16+21,84

=56,6+21,84

=78,44

Answer 3

0,78 x50 + 0,39 x 22 x 2 + 3 x 28 x 0,26

= 39 + 17,16 + 21,84

= 56,16 + 21,84

= 78