Question
A and B can finish a piece of work in 20 days and 30
days respectively. Both work on alternate days. In how many days will the work be completed when A starts the work?Solution
Both work alternately on alternate days. A starts first. Thus, 5 units can be worked in 2 days, so time taken to work 60 units = 60/5 =12 Days.
The most reactive among the halogens is-
The element used in the manufacture of safety matches is β
The nucleus of an atom consists of-
The gas used for filling weather balloons is-
The fuel that is used in modern submarines is -
Which one amongst the following is not a Green House gas?
Petroleum is a mixture of-
Which of the following is a physical change?
Urea is a β
___________ is the process in which acids and bases react to form salts and water.