In this task, you need to provide the correct option for a given problem from the provided options.

Problem: 210 students were asked in a survey if they preferred windows or mac brand computers . 60 students claimed that they preferred mac to windows brand computers . one third as many of the students who preferred mac to windows , equally preferred both brands . 90 of the students had no preference . how many of the students in the survey preferred windows to mac brand computers ? 
Options: a ) 25 , b ) 40 , c ) 50 , d ) 60 , e ) 75
b

Problem: income and expenditure of a person are in the ratio 15 : 8 . if the income of the person is rs . 15000 , then find his savings ? 
Options: a ) 6999 , b ) 7000 , c ) 7001 , d ) 7002 , e ) 7003
b

Problem: in what ratio should a variety of rice costing rs . 20 per kg be mixed with another variety of rice costing rs . 31.50 per kg to obtain a mixture costing rs . 23.75 per kg ? 
Options: a ) 16 : 30 , b ) 30 : 14 , c ) 16 : 31 , d ) 31 : 15 , e ) 15 : 31

d