# NCERT Solutions for Class 12 Maths Chapter 7 Exercise 7.4

NCERT Solutions for Class 12 Maths Chapter 7 Exercise 7.4 Integrals in English Medium as well as हिंदी मीडियम free to download in PDF or view online. Download Solutions Apps based on latest NCERT Solutions for 2019-20.

 Class 12: Maths – गणित Chapter 7: Integrals Exercise 7.4

## NCERT Solutions for Class 12 Maths Chapter 7 Exercise 7.4

### 12 Maths Exercise 7.4 Solutions

#### NCERT Solutions for Class 12 Maths Exercise 7.4 in English

NCERT Solutions for Class 12 Maths Chapter 7 Exercise 7.4 Integrals in English Medium is given below. Visit to हिंदी मीडियम or Class 12 Maths Chapter 7 main page or Top of the page.            Move to Top of the page

##### NCERT Solutions for Class 12 Maths Exercise 7.4 in Hindi

NCERT Solutions for Class 12 Maths Chapter 7 Exercise 7.4 Integrals in Hindi Medium is given below. Visit to English Medium or Class 12 Maths Chapter 7 main page or Top of the page.            Move to Top of the page

###### Questions for Practice
1. A man takes a step forward with probability 0.4 and backward with probability 0.6. Find the probability that at the end of eleven steps he is one step away from the starting point.
2. Suppose that 10% of men and 5% of women have grey hair. A grey haired person is selected at random. What is the probability that the selected person is male assuming that there are 60% males and 40% females?
3. Find P (A/B) if P(A)= 0.4, P(B)= 0.8 and P (B/A)= 0.6
4. Find P (A ∩ B) if A and B are two events such that P(A) = 0.5, P(B) = 0.6 and P (A ∪ B) = 0.8
5. A soldier fires three bullets on enemy: The probability that the enemy will be killed by one bullet is 0.7. What is the probability that the enemy is still alive?

###### Important Questions
• Bag A contains 4 red, 3 white and 2 black balls. Bag B contains 3 res, 2 white and 3 black balls. One ball is transferred from bag A to bag B and then a ball is drawn from bag B. The ball so drawn is found to be red. Find the probability that the transferred ball is black.
• Three coins are tossed once. Find the probability of getting at least one head.
• A diet for a sick person must contain at least 4000 units of vitamins, 50 units of minerals and 1400 units of calories. Two foods A and B are available at a cost of ₹5 and ₹4 per unit respectively. One unit of food A contains 200 units of vitamins, 1 unit of minerals and 40 units of calories whereas one unit of food B contains 100 units of vitamins, 2 units of minerals and 40 units of calories. Find what combination of the food A and B should be used to have least cost but it must satisfy the requirements of the sick person. What is balanced diet and what is the importance of balanced diet in daily life?