1) Kanmani ranked sixteenth from the top and twenty ninth from the bottom among those who passed an examination. Six boys did not participate in the competition and five failed in it. How many boys were there in the class?
Number of boys who passed = (15 + 1 + 28) = 44
Total number of boys in the class = 44 + 6 +5 = 55.
2) Murugan is sixth from the left end and Prasanna is tenth from the right end in a row of boys. If there are eight boys between Murugan and Prasanna, how many boys are there in the row?
Clearly, number of boys in the row = ( 6 + 10 + 8) = 24.
3) In a row of girls, Nithya and Suganya occupy the ninth place from the right end and tenth place from the left end, respectively. If they interchange their places, then Nithya and Suganya occupy seventeenth place from the right and eighteenth place from the left respectively. How many girls are there in the row?
Since Nithya and Suganya exchange places, so Rita’s new position is the same as Monika’s earlier position. This position is 17th from the right and 10th from the left. Therefore Number of girls in the row = (16 + 1 + 9) = 26.
4) In a queue of children, Arun is fifth from the left and Suresh is sixth from the right. When they interchange their places among themselves, Arun becomes thirteenth from the left. Then, what will be Suresh’s position from the right?
Since Arun and Suresh interchange places, so Arun’s new position (13th from left) is the same as Suresh’s earlier position (6th from right).
So, number of children in the queue = (12 + 1 + 5) = 18.
Now. Suresh’s new position is the same as Arun’s earlier position fifth from left.
Therefore Suresh’s position from the right = (18 – 4) = 14th.
5) Meena’s position from the right is
Meena is 6th from the left.
Number of students to the right of meena = (18 – 6 ) = 12.
So, Meena’s position is 13th from the right