# Solve the following:

(a) The teacher tells the class that the highest marks obtained by a student in her class is twice the lowest marks plus 7. The highest score is 87. What is the lowest score?

(b) In an isosceles triangle, the base angles are equal. The vertex angle is 40°. What are the base angles of the triangle? (Remember, the sum of three angles of a triangle is 180°).

(c) Sachin scored twice as many runs as Rahul. Together, their runs fell two short of a double century. How many runs did each one score?

**Solution:**

We use the concepts of simple linear equations and fundamental operations like addition, subtraction, multiplication and division to solve the problem.

(a) Highest score is 87. Let the lowest marks be x

According to question, highest marks obtained = 2x + 7

87 = 2x + 7

87 – 7 = 2x

80 = 2x

x = 40

(b) Let the base angle be b. Since the triangle is isosceles, the other base angle will also be b.

Vertex angle is given 40°.

Since, the sum of three angles of a triangle = 180° b + b + 40° = 180°

2b + 40° = 180°

2b = 180° − 40° = 140°

b = 140/2 = 70

(c) Let the score of Rahul be x, and score of Sachin be 2x According to question,

x + 2x = 198

3x = 198

x = 66

So, Rahul’s score = 66 runs

And. Sachin’s score = 2x = 132 runs

**Video Solution:**

## Solve the following: (a) The teacher tells the class that the highest marks obtained by a student in her class is twice the lowest marks plus 7. The highest score is 87. What is the lowest score? (b) In an isosceles triangle, the base angles are equal. The vertex angle is 40°. What are the base angles of the triangle? (Remember, the sum of three angles of a triangle is 180°). (c) Sachin scored twice as many runs as Rahul. Together, their runs fell two short of a double century. How many runs did each one score?

### NCERT Solutions for Class 7 Maths - Chapter 4 Exercise 4.4 Question 2

(a) x = 40, (b) b = 70, (c) Rahul’s score = 66 runs and Sachin’s score = 2x = 132 runs