The cost of 2 kg of apples and 2 kg of grapes on a day was found to be Rs. 160. After a month, the cost of 4 kg of apples and 3 kg of grapes was Rs. 300. Assuming the costs were not changed during the month, the cost of apples (per kg) will be :
1
Rs. 60
2
Rs. 20
3
Rs. 40
4
Rs.120