how to solve this?

[input](1-0.5)*1/(1-0.25)[/input]

but how did it become 2/3?

Guest:

but how did it become 2/3?

(1-0.5)*1/(1-0.25)
(1-0.5)/(1-0.25)
(1-1/2)/(1-1/4)
(2/2-1/2)/(4/4-1/4)
(1/2)/(3/4)
(1/2)*(4/3)
4/6
2/3

thank you!