Seema daily goes to a park to exercise on machines available there. When Seema spent 15 minutes on exercise b…

Seema daily goes to a park to exercise on machines available there. When Seema spent $15$ minutes on exercise bicycle and $30$ minutes on double cross walker, she received a message of burning $435$ calories on her fitness watch. When she spent $30$ minutes on exercise bicycle and $40$ minutes on double cross walker, she received a message of burning $690$ calories. To find the number of calories burned per minute on each machine, answer the following: