




In general language And means that if both the conditions is true only then the result is true, whereas in the case of Or if any one of the condition is true then the result is true. In probability, And means that the outcome has to satisfy both conditions at the same time. Or means that the outcome has to satisfy one condition, or the other condition, or both at the same time.
For example while drawing a ball from a bag of balls having 1 to 50 numbered balls
The favorable cases for getting a ball having a number divisible by 3 and 5. The favorable cases will be balls having number 15, 30, and 45 because only these number satisfy the conditions that number divisible by 3 and 5.
Whereas The favorable cases for getting a ball having a number divisible by 3 or 5. The favorable cases will be
Balls having number 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48 = 16
As all these numbers are divisible by 3 and
Balls having number 5, 10, 15, 20, 25, 30, 35, 40, 45, 50 =10
As all these numbers are divisible by 5
but we have to exclude the cases in which the number are divisible by both 3 and 5 that is 15, 30 and 45 = 3
As these numbers have appeared in the list of both cases
So the total number of favorable cases are = Favorable cases for numbers divisible by 3 + Favorable cases for numbers divisible by 5 - Favorable cases for numbers divisible by 3 and 5
= 16 + 10 - 3
= 26 - 3 = 23
A bag contains 3 red, 4 black and 10 green balls. The probability of getting a ball which is either red or green is : - | |||
| Right Option : C | |||
| View Explanation | |||
Jannat has 10 black pens 4 blue pens and 6 red pens in her pen stand, if she choose one pen at random , what is the probability that it will either be a red or a black pen ? | |||
| Right Option : A | |||
| View Explanation | |||
How many favourable outcomes are there for drawing red or a blue ball from a bag that contain 100 red balls, 30 blue balls and 50 black balls ? | |||
| Right Option : B | |||
| View Explanation | |||
Abhyas is a complete education Institute. Here extreme care is taken by teacher with the help of regular exam. Extra classes also conducted by the institute, if the student is weak.

I have spent a wonderful time in Abhyas academy. It has made my reasoning more apt, English more stronger and Maths an interesting subject for me. It has given me a habbit of self studying

One of the best institutes to develope a child interest in studies.Provides SST and English knowledge also unlike other institutes. Teachers are co operative and friendly online tests andPPT develope practical knowledge also.

It was a good experience with Abhyas Academy. I even faced problems in starting but slowly and steadily overcomed. Especially reasoning classes helped me a lot.

My experience with Abhyas academy is very good. I did not think that my every subject coming here will be so strong. The main thing is that the online tests had made me learn here more things.

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It has a great methodology. Students here can get analysis to their test quickly.We can learn easily through PPTs and the testing methods are good. We know that where we have to practice

It was good as the experience because as we had come here we had been improved in a such envirnment created here.Extra is taught which is beneficial for future.
