Level 3
The ratio of blue to purple stamps Eva had was 5 : 2. The cost of each of the blue stamps was $1 and the cost of each of the purple stamps was $2. Eva sold 40% of the blue stamps and the total cost of the unsold stamps was $455. How many blue stamps did she have left?
Level 3
Adam has 150 blue stickers and red stickers.
60% of them are blue stickers and the rest are red stickers.
When Adam buys more blue stickers,
70% of the stickers are blue stickers.
How many stickers does Adam buy?
Level 3
Adam has 200 blue stickers and red stickers.
70% of them are blue stickers and the rest are red stickers.
When Adam gives away some blue stickers,
60% of the remaining stickers are blue stickers.
How many stickers does Adam give away?
Level 3
At the ferry transit terminal, 62.5% of the passengers were male and the rest were female. After 81 female passengers entered the terminal, the percentage of the number of female passengers became 60%. Find the number of female passengers at the terminal at first.
Level 3 23 of Sean's savings comprised of 20-cent coins and 50-cent coins. Sean used some 20-cent coins to purchase a toy. The number of 50-cent coins left was 50% more than the number of 20-cent coins left. Given that Sean had 100 more 50-cent coins than 20-cent coins left in the end, find the amount of money Sean spent on the toy.
