EVERYDAY SCIENCE

Detailed explanation-1: -(i) The number of workers on a job and the time to complete the job. As the number of workers increases; the job will take less time to complete. Hence, they are inversely proportional.

Detailed explanation-2: -The number of workers and the time to complete a job is a case of direct proportion. The number of workers and the time to complete a job is a case of indirect proportion, e.g. if 160 workers can complete a work in 10 days. Then, 120 workers can complete the same work in 5 days.

Detailed explanation-3: -If two quantities are inversely proportional then as one quantity increases, the other decreases. An example of inverse proportion would be the hours of work required to build a wall. If there are more people building the same wall, the time taken to build the wall reduces.

Detailed explanation-4: -Answer:The equation for inverse proportion is x y = k or x = k/ y. Therefore, for finding the value of the constant k, you can use the known values and then use this formula to calculate all the unknown values.

Detailed explanation-5: -They are also mentioned as directly proportional or inversely proportional. The symbol used to denote the proportionality is ‘∝’. For example, if we say, a is proportional to b, then it is represented as “a ∝ b” and if we say, a is inversely proportional to b, then it is denoted as ‘a∝1/b’.