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The number of ways in which $$9$$ persons can be divided into three equal groups, is

How many integers are there such that $$2 \le n \le 100$$ and the highest common factor of $$n$$ and $$36$$ is $$1$$?

What is the next number in the series $$2,12,36,80,150?$$

The number of permutations which can be formed out of the letters of the word "SERIES" three letters together, is:

The coefficient of $$x^{18}$$ in the expansion of $$(1+x)(1-x)^{10}\{(1+x+x^2)^9\}$$ is?

Area of the triangle with vertices $$(-2,2), (1,5)$$ and $$(6,-1)$$ is 

The area of a triangle with vertices $$A(5,0),B(8,0)$$ and $$C(8,4)$$ in square units is 

If $$\dfrac{1}{6!}+\dfrac{1}{7!}=\dfrac{x}{8!}$$, then $$x=?$$

The vertices of a $$\triangle ABC$$ are $$A(3,8),B(-4,2)$$ and $$C(5,-1)$$. The area of $$\triangle ABC$$ is

The exponent of 3 in $$100!$$ is