Page 368 - Math_Genius_V1.0_C8_Flipbook

E:\Working\Focus_Learning\Math_Genius-8\Open_Files\22_Answers\Answers
\ 06-Jan-2025 Bharat Arora Proof-3 Reader’s Sign _______________________ Date __________

Practice Time 7B D. 1. False 2. True 3. True 4. False 5. False
1. `1150 2. 15% 6. False
3. Selling price of 1st electric iron = `1104 E. 1. `2522 2. Asif pays more interest of `2754
Selling price of 2nd electric iron = `1320 3. 167000 4. Gain% = 27.08% 5. `1878.2
Total profit = `24 Model Test Paper – 1
4. Gain % = 18.75% 5. Loss % = 1% 6. `888
7. Gain % = 55.56% 8. Loss % = 14.29% A. 1. (c) 2. (d) 3. (c) 4. (d) 5. (c)
9. Profit % = 25% 6. (b) 7. (c) 8. (b) 9. (b) 10. (a)
10. (a) No (b) `58,080 11. (d) 12. (a) 2
(c) C would pay less when buy directly from A. B. 1. even 2. 5% 3. n 4. 12 cm 5. `1995
Quick Check C. 1. True 2. True 3. True 4. False 5. False
2. 252, 259, 266
D. 1. 24
There is no gain or loss. 3.
Practice Time 7C
1. 25% 2. (a) `360 (b) `324
3. Set of mechanix is less expensive at store A.
4. `13,000 5. `2133.33 6. 32.5% 7. `1662.50
8. `600 9. 20% 10. 62.5%
Practice Time 7D
1. CGST = SGST = `2160 2. (a) `5722.5 (b) `1534 4.
3. 4% 4. `300 5. `35,000 6. `560 7. 919 5. 16, 32, 48 6. 48620.25, 8620.25
7. `58500 8. `18252.8 34% 8. 30°
Maths Fun 10. (a) 30 (b) 60 (c) 10% (d) 40%
Chapter 8: Algebraic Expressions
Time Period (years) SI (in `) CI (in `) Let’s Recall
1 50 50 1. 3, –5, 7, –6 2. a b and 7a b
3 2
3 2
2 100 103 3. 4a – 4ab + 3b 4. 5 5. 5.124
2
2
3 150 158 Quick Check
4 200 216 2 2 2
5 250 276 1. 4qp, 3 pq 2. xy , 16xy
Think and Answer
Y
300 SI Scale: Y-axis: 1 unit = `25 6a – 15b + 10c
275 CI Practice Time 8A
250
2
225 1. (a) Terms: 9ab, –5b , 1; Coefficients: 9, –5
200 (b) Terms: 11xyz, –6yz, xy; Coefficients: 11, –6, 1
2 2
2
175 (c) Terms: 7m n , 8mn , –4mn, –3; Coefficients: 7, 8, –4
150
2
) 125 2. (a) x – x + 10
Interest (` 100
75
50 Terms → x 2 –x 10
25 (Variable) (Variable) (Constant)
1 year 2 years 3 years 4 years 5 years X
Time (in years) Factors → x x –1 x
Practice Time 7E (b) 8yz – 2y + 7
1. (a) Amount = `5832; CI = `832
(b) Amount = `11576.25; CI = `1576.25 Terms → 8yz –2y 7
(c) Amount = `19483.77; CI = `1483.77 (Variable) (Variable) (Constant)
2. Amount = `69431.25
3. Kavita pays more interest by `725. Factors → 8 y z –2 y
4. `208 5. 231525 6. 312500 (c) 2 2 2
7. `484000 8. 10% 9. 2 years 10. `25,000 8p + q – 2r + 5
11. `13716.48 12. 20%
Maths Connect Terms → 8p 2 q 2 –2r 2 5
1. Required ratio = 9 : 20 2. 2454.54 mg 3. 50% (Variable) (Variable) (Variable) (Constant)
Mental Maths Factors → 8 p p q q –2 r r
1. 36% 2. `200 3. `1408 4. 14 years 3. Like terms: 24x y, –7yx , 55x y
2
2
2
5. The new price is 9% less than the initial price. 6. 25% profit Unlike terms: 17y x , 99y x
3 2
2 3
Chapter Assessment 4. (a) Binomial (b) Monomial (c) Binomial (d) Trinomial
A. 1. (b) 2. (d) 3. (a) 4. (c) 5. (a) (e) Trinomial
6. (b) 7. (a) 8. (c) 5. (a) 54 (b) 2 (c) 3 (d) 6 (e) 9
2 3
B. 1. (a) 2. (a) 3. (d) 6. (a) 32x – 28y – 30z 2 (b) 9a + 17b (c) –18a b
2
4
2
3
C. 1. `2500 2. 15 3. Tax 4. Overhead 7. (d) –p – 10p – 2p – 6p – 5 (e) 70m n – 21mn – 35mn 2 2
2 2
2
2 2
(a) x – y + 18z
(b) 10a b + 15ab (c) –14a b c + 2ab c + 7a bc
2
5. 6 % 6. `1995 (d) –11m n + 7m + 3 (e) 11pqr – 6p + 6q – 2r 3
3
2
3
2 2
3 8. –2ab – 34bc + 40ac – 10abc
Mathematics-8 366