\[\boxed{\mathbf{3.}\mathbf{276.ОК\ ГДЗ - домашка\ на\ }5}\]
\[\textbf{а)}\ 100 - 1 = 99\ :3 =\]
\[= 33 + 27 = 60\ :4 =\]
\[= 15 + 135 =\]
\[= 150\ :25 = 6 + 14 =\]
\[= 20 \cdot 5 = 100\]
\[\textbf{б)}\ 90 - 45 = 45\ :15 =\]
\[= 3 + 13 = 16 \cdot 5 = 80\ :20 =\]
\[= 4 + 26 = 30 \cdot 3 = 90\ :1 = 90\]