Chapter 13 Symmetry Ex 13.1
Chapter 13 Symmetry Ex 13.1 Question 1. List any four symmetrical objects from your home or school. Solution: The following objects can be symmetrical: (a) Notebook (b) Dinning table (c) A blackboard (d) Wall clock (e) A pair of scissors Question 2. For the given figure, which one is the mirror line, l1 or l2? Solution: […]
Chapter 12 Ratios and Proportions Ex 12.3
Chapter 12 Ratios and Proportions Ex 12.3
Chapter 12 Ratios and Proportions Ex 12.2
Chapter 12 Ratios and Proportions Ex 12.2 Question 1. Determine if the following are in proportion, (a) 15, 45, 40, 120 (b) 33, 121, 9, 96 (c) 24, 28, 36, 48 (d) 32, 48, 70, 210 (e) 4, 6, 8, 12 (f) 33, 44, 75, 100 Solution: ∴ 15 : 45 :: 40 : 120 […]
Chapter 12 Ratios and Proportions Ex 12.1
Chapter 12 Ratios and Proportions Ex 12.1 Question 1. There are 20 girls and 15 boys in a class. (a) What is the ratio of the number of girls to the number of boys? (b) What is the ratio of the number of girls to the number of students in the class? Solution: (a) Number […]
Chapter 12 Ratio and Proportion
Chapter 12 Ratio and Proportion Very Short Answer Type Question 1. Find the ratio of 75 cm to 1.5 m. Solution: The given numbers are not in the same units. So, converting them into same units. 1.5 m = 1.5 x 100 cm = 150 cm [∵ 1 m = 100 cm] ∴ The required […]
Chapter 11 Algebra
Chapter 11 Algebra Very Short Answer Type Question 1. Six less than a number equals to two. What is the number? Solution: Let the number be ‘x’. According to condition, we have x – 6 = 2 By inspections, we have 8 – 6 = 2 ∴ x = 8 Thus, the required number is […]
Chapter 11 Algebra Ex 11.5
Chapter 11 Algebra Ex 11.5 Question 2. Complete the entries in the third column of the table. S. No. Equation Value of variable Equations satisfied Yes /No (a) 10y = 80 y = 10 (b) 10y = 80 y = 8 (c) 10y = 80 y = 5 (d) 4l = 20 l = 20 (e) […]
Chapter 11 Algebra Ex 11.4
Chapter 11 Algebra Ex 11.4 Question 1. Answer the following: (a) Take Sarita’s present age to bey years. (i) What will be her age 5 years from now? (ii) What was her age 3 years back? (iii) Sarita’s grandfather is 6 times her age. What is the age of her grandfather? (iv) Grandmother is 2 […]
Chapter 11 Algebra Ex 11.3
Chapter 11 Algebra Ex 11.3 Question 1. Make up as many expressions with numbers (no variables) as you can from three numbers 5, 7 and 8. Every number should be used not more than once. Use only addition, subtractions and multiplication. Solution: Given numbers are 5, 7 and 8. Expressions are: (i) 8 + (5 […]
Chapter 11 Algebra Ex 11.2
Chapter 11 Algebra Ex 11.2 Question 1. The side of an equilateral triangle is shown by l. Express the perimeter of the equilateral triangle using l. Solution: Given that the side of an equilateral triangle = l Perimeter of the equilateral triangle = 3 x side = 3 x l = 3 l units Question […]