Level 3
A bus had some passengers at the beginning. After 10 passengers alighted from the bus and another 46 passengers boarded the bus, there were two times as many passengers as before. How many passengers were there on the bus at first?
Level 3
There were 3 similar big boxes of the same mass. There were another 4 similar small boxes of the same mass. The total mass of the big and small boxes was 90 kg. The mass of a big box was twice the mass of a small box. Find the total mass of a big box and a small box.
