①5÷2
1
4 +4×20%,
=
20
9 +
4
5 ,
=
136
45 ;
答:和是
136
45 .
②设这个数是x,由题意得:
(1-25%)x=40×(1+50%),
75%x=40×150%,
75%x=60,
75%x÷75%=60÷75%,
x=80;
答:这个数是80.
①5÷2
1
4 +4×20%,
=
20
9 +
4
5 ,
=
136
45 ;
答:和是
136
45 .
②设这个数是x,由题意得:
(1-25%)x=40×(1+50%),
75%x=40×150%,
75%x=60,
75%x÷75%=60÷75%,
x=80;
答:这个数是80.