Present age of Ashok is twice the present age of Kishan. After 7 years the Kishan’s age will be 4 times of the Kartik’s present age. If Kartik celebrated his 9th birthday 3 years ago, then what will be the present age (in years) of Ashok?
If price of an article decreases from Rs 40 to Rs 30, quantity demanded increases from Q1 units to 7500 units. If point elasticity of demand is -1 find Q1?