Word problems: show steps, and answer each question in a complete sentence.
1) After three shipments, for cars carried 960 bags of cement in all. What is the average number of bags of cement per car in each shipment?
2) The five digit number 3A,51B is a multiple of 10. List all the possible values of A if the number is also divisible by three.
1) To find the average number of bags of cement per car in each shipment, we need to divide the total number of bags by the number of cars. Since 960 bags were carried in 3 shipments, we calculate 960 bags / 3 cars = 320 bags in each car on average.
2) The number 3A,51B is divisible by 10 if B is 0. Since the number is also divisible by 3, we need to find possible values of A that make the number a multiple of 3. The sum of the digits of the number is 3 + A + 5 + 1 + B, which must be divisible by 3. If B is 0, then A must be either 3 or 6 to make the sum divisible by 3. Therefore, the possible values of A are 3 and 6.