①0.65×14+87×65%?
13 20
=0.65×14+87×0.65-0.65,
=0.65×(14+87-1),
=0.65×100,
=65;
②(
?2 3
+1 2
)÷1 6
1 24
=(
-2 3
+1 2
)×24,1 6
=
×24-2 3
×24+1 2
×24,1 6
=16-12+4,
=8;
③76×(
?1 23
)+23×(1 53
+1 53
)?53×(1 76
?1 23
).1 76
=76×
-76×1 23
+23×1 53
+23×1 53
-53×1 76
+53×1 23
,1 76
=
-76 23
+76 53
+23 53
-23 76
+53 23
,53 76
=(
?76 23
)+(53 23
+23 76
)-(53 76
-76 53
),23 53
=1+1-1,
=1.