Ticket for an adult is Rs 2200 and a child is Rs 990. One child goes free with two adults. If a group has 23 adults and 11 children, what is the discount the group gets?

Step 1: Calculate the standard total cost without any discount offer.
$$\text{Cost of 23 adults}=23\times 2200=\text{Rs }50,600$$
$$\text{Cost of 11 children}=11\times 990=\text{Rs }10,890$$
$$\text{Total Standard Price}=50600+10890=\text{Rs }61,490$$
Step 2: Calculate the discount value based on the offer.The offer states: 1 child goes free with every 2 adults.With 23 adults, the maximum number of pairs of adults is:
$$\lfloor 23/2\rfloor =11\text{ pairs}$$
Since there are 11 children in the group, all 11 children can go completely free under this offer.
$$\text{Total Discount received}=\text{Cost of 11 children}=\text{Rs }10,890$$
Step 3: Calculate the discount percentage.
$$\text{Discount Percentage}=\left(\frac{10890}{61490}\right)\times 100\approx 17.71\%$$