For the following questions answer them individually
What is the greatest possible length of a scale (in cm) that can be used to measure exactly three cloths of lengths 3m, 5.1 m and 12.9m?
The average of 5 consecutive even integers is 38. What is the product of first and the fifth numbers?
The desending order of the numbers $$\frac{7}{8}, \frac{5}{6}, \frac{3}{4} and \frac{8}{9}$$ is
The gross income of a person is Rs.22 lakhs. A part of the income is exempted from the tax. The rest of the income is taxed at 30%. If his income after deduction of tax is 19 lakhs, what is the income (in lakhs) exempted from tax?