Average Mixture & Alligation Level-3 Quiz-1

1. In a company there are 252 employees, in which the ratio of the number of men and women is 2 : 1. Some more women are employed and the ratio of men and women becomes 1 : 1. The average age of all the employees is now 22 years and the average age of the women is 2 years less than the average age of the men. Find the average age (in years) of men and women.

2. Alloy Ι contains 30% zinc, 40% copper and the remaining is gold. Alloy II contains 40% tin and some zinc and gold. On mixing these two alloys in a certain ratio, Alloy IIΙ, which has 30% zinc and 25% tin is obtained. If equal weights of both Alloy Ι and Alloy IIΙ are mixed, then what percentage of the alloy formed will be copper?

3. In the previous question, Find the percentage of gold in the new alloy, formed by mixing Alloy II and Alloy IIΙ in a certain ratio.

4. There are two positive quantities a and b satisfying the relationship (a + x) (b – x) = 64. Which of the following statements can be true?

5. Find the average of all the three-digit numbers whose units digit is half the hundreds digit.

6. There is a 40 liters solution of milk and water in which milk forms 72%. How much water must be added to this solution to make it a solution in which milk forms 60%? (in liters)

7. Two varieties of coffee—A and B are mixed in the ratio 3 : 2. The mixture is sold at Rupees 100 per kg at 100% profit. If variety A costs Rupees 10 per kg more than variety B, what is the cost of variety B per kg?

8. In a class, the average height of the boys lies between 100 cm and 120 cm. The average height of the girls lies between 80 cm and 100 cm. If there are 90 boys and 60 girls in the class, the average height of the class (in cm) definitely lies in which of the following ranges?

9. Two varieties of rice A and B priced at Rupees 6.75 per kg and Rupees 9.75 per kg, respectively were mixed and sold at Rupees 10.80 per kg at a profit of 20%. Find the ratio in which A and B are mixed.

10. The average age of the employees in a company is 40 years. If six new persons with an average age of 30 years joined and 5 employees with an average age of 40 years left the company, then the average age of the entire company would decrease by 5 years. Find the number of employees in the company.