Level 3
The ratio of Yvette's money to Linda's money was 1 : 3. After Yvette spent thrice as much as Linda, Yvette and Linda had $6 and $42 left respectively. Find the amount of money each of the girls have at first.
Level 3
Betty spent 45 of her money on 14 stamps and 5 pens. The cost of each pen is 2 times the cost of each stamp. She bought some more stamps with 23 of her remaining money. How many stamps did Betty buy altogether?
Level 3
Carl had a total of 90 notes. The notes are $10 notes and $5 notes. After he spent 20% of the $10 notes and 60% of the $5 notes on a stereo system, he was left with 4 times as many $5 notes as $10 notes. How much did the stereo system cost?
