You will spend less time compared to you. Second, you have 30 minutes to solve these; are you taking the entire 30 minutes or are you giving up before the 30 minutes elapse?
Uds. emplearán menos tiempo que Uds. Otra, es que tienen 30 minutos para resolverlos ¿Se toman los 30 minutos o se dan por vencidos antes de los 30 minutos?