In a toy company, it requires 36 machines to produce a car toys in 54 days. How many machines would be required to produce the same number of car toys in 81 days? 

6 If a box of pens is given to 25 children, they will get 2 pens each. How many would each get, if the number of children is reduced by 10?  7 A batch of tablets were packed in 10 boxes with 6 tablets in each box. If the same batch is packed using 12 tablets in each box. How many boxes would be needed? 9 Two persons could fit the AC unit in a house in 2 days one person fell ill before the work started, how long would the job take now? 10 In a college 7 period a day each of 45 minutes duration. How long each period be, if the school has 9 periods a day assuming the number of hours to be the same?