Level 3
A box containing 60 folders had a mass of 5.01 kg. A box containing 25 post-it-pads has a mass of 6.21 kg. The mass of each post-it-pad was thrice that of each folder. Find the mass of the empty box in grams.
Level 3
Marion had some red and pink marbles. If she gives away 16 red marbles, the number of red marbles will be 10% of the total number of marbles left. If she gives away 48 pink marbles, the number of red marbles will be 25% of the total number of marbles left.
Level 3
Jane and Tina had $652. Tina had $76 more than Jane. Jane spent 2 times as much as Tina and was left with 23 as much as Tina. How much did Jane spend?
Level 3
When an ice box is packed with 25 identical bottles of soda, it has a mass of 18.4 kg. When the ice box is packed with 30 identical packets of milo, it has a mass of 7.5 kg. A bottle of soda weighs 470 g more than a packet of milo. What is the mass of the empty ice box in kg?
Level 3
At the bird park were some adults. 12 of the number of tourists was equal to 2 times the number of locals. When another 19 tourists entered and 51 tourists left, the ratio of the number of tourists to the number of locals become 7 : 2. Find the number of tourists at the bird park at first.
