Maths Answers Class 10 Ncert

ANSWERS/HINTS

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APPENDIX 1 ANSWERS/ HINTS
EXERCISE 1.1
1. (i) 45 3. 8 columns 4. An integer can be of the form 3q, 3q + 1 or 3q + 2. Square all of these integers. 5. An integer can be of the form 9q, 9q + 1, 9q + 2, 9q + 3, . . ., or 9q + 8. (ii) 196 (iii) 51 2. An integer can be of the form 6q, 6q + 1, 6q + 2, 6q + 3, 6q + 4 or 6q + 5.

EXERCISE 1.2
1. 2. 3. (i) 2 × 5 × 7 (iv) 5 × 7 × 11 × 13 (i) LCM = 182; HCF = 13 (i) LCM = 420; HCF = 3
2

(ii) 22 × 3 × 13 (v) 17 × 19 × 23 (ii) LCM = 23460; HCF = 2 (ii) LCM = 1139; HCF = 1 7. 36 minutes

(iii) 32 × 52 × 17 (iii) LCM = 3024; HCF = 6 (iii) LCM = 1800; HCF = 1

4. 22338

EXERCISE 1.4
1. (i) Terminating (iii) Non-terminating repeating (v) Non-terminating repeating (vii) Non-terminating …show more content…

(ii) x – y = 18, x + y = 180, where x and y are the measures of the two angles in degrees; x = 99, y = 81. (iii) 7x + 6y = 3800, 3x + 5y = 1750, where x and y are the costs (in Rs) of one bat and one ball respectively; x = 500, y = 50. (iv) x + 10y = 105, x + 15y = 155, where x is the fixed charge (in Rs) and y is the charge (in Rs per km); x =5, y = 10; Rs 255. (v) 11x – 9y + 4 = 0, 6x – 5y + 3 = 0, where x and y are numerator and denominator of the fraction;
7 ( x = 7, y = 9). 9

(ii) s = 9, t = 6 (v) x = 0, y = 0

(iii) y = 3x – 3, (vi) x = 2, y = 3

where x can take any value, i.e., infinitely many solutions.

(vi) x – 3y – 10 = 0, x – 7y + 30 = 0, where x and y are the ages in years of Jacob and his son; x = 40, y = 10.

EXERCISE 3.4
1. (i) x =
19 6 , y= 5 5

(ii) x = 2, y = 1

(iii) x =

9 5 ,y= − 13 13

(iv) x = 2, y = –3 2. (i) x – y + 2 = 0, 2x – y – 1 = 0, where x and y are the numerator and denominator of the fraction;
3 ⋅ 5

(ii) x – 3y + 10 = 0, x – 2y – 10 = 0, where x and y are the ages (in years) of Nuri and Sonu respectively. Age of Nuri (x) = 50, Age of Sonu (y) = 20. (iii) x + y = 9, 8x – y = 0, where x and y are respectively the tens and units digits of the number; 18. (iv) x + 2y = 40, x + y = 25, where x and y are respectively the number of Rs 50 and Rs 100 notes; x = 10, y = 15. (v) x + 4y = 27, x + 2y = 21, where x is the fixed charge (in Rs) and y is the additional charge (in Rs) per day; x