 
 <translate> Reconstruct a question, answer pair from this explanation: If each of the 20 customers bought 15 marbles, then they bought 20 * 15 = 300 marbles in total from Mr Julien's store. The number of marbles remaining in the store is 400 - 300 = 100 marbles.
 <hau> Sake gina tambaya, amsa ma'aurata daga wannan bayani: Idan kowane daga cikin abokan ciniki 20 ya sayi marbles 15, to, sun sayi 20 * 15 = 300 marbles a duka daga kantin sayar da Mr. Julien. Adadin marbles da suka rage a cikin shagon shine 400 - 300 = marbles 100. 