A retailer offers the following discount scheme to his customers for the purchase of articles. ‘Buy 30 and get 10 free’ Find the discount percentage offered.

A retailer offers the following discount scheme to his customers for the purchase of articles. ‘Buy 30 and get 10 free’ Find the discount percentage offered.
एक खुदरा विक्रेता अपने ग्राहकों को वस्तुओं की खरीद पर निम्नलिखित छूट योजना प्रदान करता है: ‘30 खरीदें और 10 मुफ़्त पाएं’। दी गई छूट का प्रतिशत ज्ञात कीजिए।