Level 2
Sam, Ken and Don had a total of $108. Ken had twice as much money as Sam. Don had thrice as much money as Ken. How much more money did Don have than Ken?
Level 2
The total cost of a watch, a radio and a calculator is $270. The radio costs thrice as much as the calculator. The watch costs twice as much as the radio. Find the difference in the cost between the watch and the radio.
Level 3
The total cost of 2 identical cups, 3 identical plates and 1 bowl is $116. The total cost of 3 such plates and the bowl is $64. The cost of 1 cup is twice as much as the cost of 1 plate. What is the total cost of the 3 plates?