84. Arrange 64 students of 10th class in rows in such a way that the number of rows and number of
students are equal. Find the number of students in each row.

89. The relation between time and water pulled by a water pump is direct. If a pump raised 600 liters
water in 45 minutes, how much water it will raise in 1 hour.

99. A survey showed that the colour of cars chosen by people silver, white and black were in ratio of 7
: 4 : 2 respectively. If a dealer has sold 1300 cars in a year. How many cars of each colour did he
sell?