what is 66and 2/3rds * 8

8(66+2/3)

=8*66+8*2/3

=528+16/3

=528+5+1/3

=533 and 1/3

check

$$\left({\mathtt{66}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{2}}}{{\mathtt{3}}}}\right){\mathtt{\,\times\,}}{\mathtt{8}} = {\frac{{\mathtt{1\,600}}}{{\mathtt{3}}}} = {\mathtt{533.333\: \!333\: \!333\: \!333\: \!333\: \!3}}$$