1. **Problem:** A shopkeeper earns a profit of 70 for every 3 bags of wheat sold. How many bags must be sold to make a profit of 1400? 2. **Formula:** Profit per bag = \frac{70}{3} 3. **Set up equation:** Let the number of bags be $n$. Total profit = Profit per bag $\times n$. 4. **Equation:** $$\frac{70}{3} \times n = 1400$$ 5. **Solve for $n$:** $$n = \frac{1400 \times 3}{70}$$ 6. Simplify numerator and denominator: $$n = \frac{4200}{70} = 60$$ 7. **Answer:** The shopkeeper must sell 60 bags to make a profit of 1400. **Final answer:** B) 60