Respectively understand: the remainder of three or three numbers is multiplied, that is, 2 times 70, the remainder of five or five numbers is multiplied, 3 times 2 1, the remainder of seven or seven numbers is multiplied, and 2 times 15, and then the respective numbers are added. If it is less than or equal to 105, it is the answer. If it is greater than 105, subtract 105, that is, (2 * 70.