Reduction In Salary Due To Reduction In Working Hours

Hello
I need your valuable advice.Recently one our Female employee has requested us, that her working hours should be reduced to 7 from 9 hours daily so that she can manage her work and home.
I want to know that should her ,salary also be reduced.If yes,how much should be the reduction in her salary.
Regards
Harpreet

If there is a mutual understanding and consent between both the employer and employee then I think you may proceed with the reduction in working hours and salary.
Calculate her current salary per hour...and reduce it by two hours per day and fix new salary figures and issue a letter to her.

Can any one please share any format for the same???