The topic ratio and proportion plays a major role quantitative aptitude test. There is no competitive exam without the questions from this topic. We have already learned this topic in our lower classes.Even though we have been already taught this topic in our lower classes, we need to learn some more short cuts which are being used to solve the problems in the above topic.
The only thing we have to do is, we need to apply the appropriate short cut and solve the problems in a limited time. This limited time will be one minute or less than one minute in most of the competitive exams.
|1. a/b is the ratio of a to b. that is a:b.|
| 2. When two ratios are equal, they are said to be in proportion.
If a/b = c/d, then a,b,c,d are in proportion. It can be written as a:b=c:d.
|3. Cross product rule in proportion. Product of the extremes = product of the means. That is ad= bc.|
|4. If two ratios are inverse to each other, then the product of those two ratios will be 1 or 1:1.|
|5. If “a” is directly proportional to “b”, then it can be written as a=kb.
If “a” is inversely proportional to “b”, then it can be written as a=k/b.
|6. If “m” kg of one kind costing “a” rupees/kg is mixed with “n” kg of another kind costing “b” rupees/kg.
Then the price of the mixture is = (ma+nb)/(m+n).
|7. If one quantity increases or decreases in the ratio a:b, then the new quantity is = b of the original quantity/a.
That is new quantity = (“b” x original quantity) /a.
Students who are preparing to improve their aptitude skills and those who are preparing for this type of competitive test must prepare this topic in order to have better score. Because, today there is no competitive exam without questions from the topic ratio and proportion . Whether a person is going to write placement exam to get placed or a students is going to write a competitive exam in order to get admission in university, they must be prepared to solve time and work problems. This is the reason for why people must study this topic.
As we mentioned in the above paragraph, a person who wants to get placed in a company and a students who wants to get admission in university for higher studies must write competitive exams like placement test and entrance exam. To meet the above requirement, it is very important to score more marks in the above mentioned competitive exams. To score more marks, they have to prepare this topic. Preparing this topic would definitely improve their marks in the above exams. Preparing this topic is not difficult task. We are just going to remember the stuff that we have already learned in our lower classes
Students have to learn few basic operations in this topic time and work and some additional tricks. Already we are much clear with the four basic operations which we often use in math. They are addition, subtraction, multiplication and division. Even though we are much clear with these four basic operations, we have to be knowing some more stuff to do the problems which are being asked from this topic in competitive exams. The stuff which I have mentioned above is nothing but the tricks and shortcuts which need to solve the problems in a very short time.
Short cut is nothing but the easiest way to solve problems related to time and work. In competitive exams, we will have very limited time to solve each problem. Then only we will be able to attend all the questions. If we do problems in competitive exams in perfect manner with all the steps, it will definitely take much time and we may not able to attend the other questions. So we need some other way in which the problems can be solved in a very short time. The way we need to solve the problem quickly is called as shortcut.
Here, we are going to have some problems on ratio and proportion. You can check your answer online and see step by step solution.
1. The average age of three boys is 25 years and their ages are in the proportion 3:5:7. The age of the youngest boy is