In an exam 4 marks are awarded for each correct answer, and 2 marks are deducted for each incorrect answer. If Kanya attempts 32 questions and scores 68 marks, find the number of correct answers.

Following chart shows marks obtained by students in Science examination. If first division is awarded for 60 or above marks, find the number of students who got first division in the exam.

A shopkeeper sells two qualities of sugar at the rates of ฿33 per kg. and ฿42 per kg, gaining 10% and 20% profit respectively. If he mixes the two variants in the ratio 1:4 and sells the mixture at ฿40.8 per kg., what is his gain or loss?

Train X takes 36 hours to travel from station A to station B, while train Y takes 45 hours to travel from station B to station A. If train X and Y starts at same time from stations A and B respectively, after what time will they cross each other? (Assume trains travel with uniform speed)

The cost of a doll is a two digit number (for example ฿xy). Its selling prices has same digits as cost with digits interchanged (฿yx). If its profit margin is divided by 9, find the remainder of division.

Phailin measures the heights of 10 of her friends as follows (in centimetres) 150 , 151 , 129 , 132 , 159 , 150 , 144 , 143 , 113 , 153 What is the average of their heights?