Answer:
25
%
o
f
40
=
25
100
×
40
=
10
discount
price =
40
−
10
=
$
30
Second method. Find 75% immediately
75
%
o
f
40
=
75
100
×
40
=
$
30
You can do any percentage question using the concept of direct proportion.
40
100
=
x
75
if $40 is 100%, how much is 75%?
100
x
=
75
×
40
cross-multiply
x
=
75
×
40
100
this a possible expression for the sale price
x
=
$
30
Explanation: