Permutations an...

In a chess tournament each of six players will play every other player exactly once. How many matches will be played during the tournament? 

If the area of the triangle formed by $$ (-2,5), (x,-3) $$ and $$(3,2)$$ is $$14 $$ square units, then $$x=$$ ____.

ab _ bc _ c _ ba _ c

If CAT is $$48$$,  Z is $$52$$ Then what  is TEA equal to ?

I think of a decimal number. After I have subtracted 2.9 from it, then multiplied by 3 and then added 0.15, I get 10.5. What is the decimal number? 

I thought of a decimal number. After I had multiplied it by 2, then added 1.5 and then divided by 3, I got 3.5. What was the decimal number? 

In a class there are 18 boys who are over 160 cm tall If these constitute three-fourths of the boys and the total number of boys is tow-third of the total number of students in the class what is the number of girls in the class?

Out of 100 students 50 fail in English and 30 in Maths. If 12 students fail in both English and Maths, then the number of students passing both the subjects is

At the end of a business conference, the ten people present all shake hands with each other once. How many handshakes will there be altogether? 

Answer the following set of questions by reading the above pitctograph. Number of TV sets sold in the year 2005 is