①987+104×65-1747,
=(1000-13)+(100+4)×65-1747,
=1000-13+6500+260-1747,
=1000-13+6500+200+60-1700-47,
=(1000+6500+200-1700)+(60-13-47),
=6000+0,
=6000;
②
37
63 ÷7+
1
7 ×
26
63
=
37
63 ×
1
7 +
1
7 ×
26
63 ,
=(
37
63 +
26
63 )×
1
7 ,
=1×
1
7 ,
=
1
7 ;
③(
7
9 +
4
21 -
3
7 )×6.3,
=
7
9 ×6.3+
4
21 ×6.3-
3
7 ×6.3,
=4.9+1.2-2.7,
=3.4;
④15÷[(
5
7 -
1
2 )÷
3
28 ]-0.5,
=15÷[
3
14 ×
28
3 ]-0.5,
=15÷2-0.5,
=7.5-0.5,
=7.