Assignment:
Q1. Joe has a collection of nickels and dimes that is worth $5.65. If the number of dimes was doubled and the number of nickels was increased by 8, the value of the coins would be $10.45. How many dimes does he have?
Q2. An express train and a local train leave GraysLake at 3 P.M. and head for Chicago 50 miles away. The express travels twice as fast as the local and arrives 1 hour ahead of the local. Find the speed of each train.
Q3. Walt made an extra $9000 last year from a part-time job. He invested part of the money at 9% and the rest at 8%. He made a total of $770 in interest. How much was invested at 8%?
Provide complete and step by step solution for the question and show calculations and use formulas.