\[\boxed{\text{151.}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[30 \cdot 16 = 30 \cdot (10 + 6) =\]
\[= 30 \cdot 10 + 30 \cdot 6 =\]
\[= 300 + 180 = 480.\]
\[15 \cdot 42 = (10 + 5) \cdot 42 =\]
\[= 10 \cdot 42 + 5 \cdot 42 =\]
\[= 420 + 210 = 630.\]
\[36 \cdot 11 = 36 \cdot (10 + 1) =\]
\[= 36 \cdot 10 + 36 \cdot 1 =\]
\[= 360 + 36 = 396.\]
\[60 \cdot 42 = 60 \cdot (40 + 2) =\]
\[= 60 \cdot 40 + 60 \cdot 2 =\]
\[= 2\ 400 + 120 = 2\ 520.\]
\[70 \cdot 25 = 70 \cdot (20 + 5) =\]
\[= 70 \cdot 20 + 70 \cdot 5 =\]
\[= 1\ 400 + 350 = 1\ 750.\ \]