Найти значение выражения:
1) 12√1200-25√2700-0,4√243=
2) -10√100+6√847+2,9√25-11√252=
3)√675-7√507-3,4√1875+√30000=

1) $frac{1}{2} sqrt{1200}- frac{2}{5} sqrt{2700}- 0,4sqrt{243}= frac{1}{2}*20sqrt{3}- frac{2}{5}*30sqrt{3}- 0,4*9sqrt{3}=$ $=10sqrt{3}-12sqrt{3}-3,6sqrt{3}=-5,6sqrt{3}$
2) $-10sqrt{100}+6sqrt{847}+2,9sqrt{25}-11sqrt{252}=$
$-100+66sqrt{7}+14,5-66sqrt{7}=-85,5$
3) $sqrt{675}-7sqrt{507}-3,4sqrt{1875}+sqrt{30000}=$
$15sqrt{3}-91sqrt{3}-85sqrt{3}+100sqrt{3}=-61sqrt{3};$