Answer : 3. "2:1"
Explanation :

Answer: C) 2:1 Explanation: Given rate of wheat at cheap = Rs. 2.90/kg Rate of wheat at cost = Rs. 3.20/kg Mixture rate = Rs. 3/kg Ratio of mixture =            2.90                              3.20                               3 (3.20 - 3 = 0.20)            (3 - 2.90 = 0.10)   0.20 : 0.10 = 2:1   Hence, wheat at Rs. 3.20/kg be mixed with wheat at Rs. 2.90/kg in the ratio of 2:1, so that the mixture be worth Rs. 3/kg.