1. Find the third proportion to the number 9 and 6.
2. Two numbers are in the ratio 3:7. If sum of these two numbers is 180, find the difference between the numbers.
3. If sum of three numbers is 171 and the ratio between the first and second be 3:5 and that between second and third be 4:5 then find the second number.
4. A bag contains an equal number of 50-paise, 25-paise, 20-paise coins. If the total amount is Rs. 60, how many coins of each type are there ?
5. The ratio of two numbers is 11:7. If each number be decreased by 3, the two numbers are in the ratio 5:3. Find the numbers.
6. The ratio of income of two persons is 7:4 and that of their expenditure is 3:5. Find the income of each person, if they save Rs. 460 and Rs. 230 respectively.
7. Divide Rs. 2160 into three parts in such a way that half of the first part, one-third of the second part and one-seventh of the third part are equal.
8. After an increament of 5 in both the numerator and denominator, a fraction changes to \(\frac{4}{5}\). Find the original fraction.
9. The student in classes of a school are in the ratio 3:5:7. If 30 student are increased in each class, the ratio changes to 3:4:5. Find total number of students in each class before increase.
10. If \(\frac{1}{x}:\frac{1}{y}:\frac{1}{z}\) = 3:4:5 then find x : y : z.