By using sin you can find BD. Sin is the opposite side/ hypotenuse. This can be simplified to BD = opposite (4) divided by sin(27). 27 is the angle.
Sin A=Cos (90º-A)
Then:
sin 30º=cos (90º-30º)=Cos 60º=1/2
Answer: cos 60º=1/2
So he gives 1/4 to his brother 220/4=55 then then he sells the 20% which is 220*.20=44 and then 15 he takes to his friends so if you add those you get 55+44=99+15=114 then subtract this number from the total 220-114=106