Answer :

40% from 25 is:

25 * 40% =
= 25 * 40/100 =
= 25 * 4/10 =
= 25 * 0,4 =
= 10

Another way is to find 1% of 25 and then multiply it by 40:

25 * 40% =
= (25 / 100) * 40 =
= 0,25 * 40 =
= 10