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Page 1: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

1 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

Page 2: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

2 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

Solutions S1. Ans.(a)

Sol. Cost price of mixture = 80 ×100

150

= 160

3

Milk

Water=

160

140

=8

7

∴ Water: Milk = 7: 8

S2. Ans.(d)

Sol. Let annual rate is r%

∴ r = 100 × 294

8400 × 1 = 3.5%

∴Sum at 4%

Sum at10

3%

=

1

61

2

=1

3

∴ Sum at 4% = 1

4× 8400

= Rs. 2100

S3. Ans.(b)

Sol. Let x g sugar is added

Original sugar = 600 ×40

100

= 240 g (240+x)

(600+x)× 100 = 50

⇒ 480 + 2x = 600 + x

⇒ x = 120g

Page 3: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

3 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S4. Ans.(b)

Sol. According to the law of allegation,

Land at 6% loss

Land at x% profit=

x − 10

16⇒

2

53

5

=x − 10

16

2

3=

x − 10

16⇒ x =

62

3%

S5. Ans.(c)

Sol. C.P. of mixture of sugar = 30 ×100

110=

300

11rupee kg⁄

According to law of mixture

∴sugar1

sugar2=

30

25=

6

5

∴ Quantity of sugar 1 =6

5× 30 = 36 kg

S6. Ans.(e)

Sol. Selling price of T. V. = 12000 ×88

100= 10,560

Selling price of mobile phone = 10000 ×108

100= 10800

∴ Total selling price = 10,560 + 10,800 = 21360

Total purchasing price = 12,000 + 10,000 = 22,000

∴ Loss = 22,000 − 21,360 = Rs. 640

S7. Ans.(b)

Sol. Cost price of wrist watch = 2,400 ×100

75= 3200

∴ Selling price of wrist watch when sold at 25% profit

= 3200 ×125

100= Rs. 4,000

Page 4: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

4 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S8. Ans.(c)

Sol. By allegation rule,

So, ratio in which two alloy should be mix = 1 : 5

Total new alloy = 42 kg.

So, required answer = 7 kg. & 35 kg.

S9. Ans.(d)

Sol. Let total distance = d km

∴ Average speed =d

d

120+

d

120+

d

40

= 24 km hr⁄

S10. Ans.(a)

Sol. Let 5 consecutive odd numbers are x–4, x–2, x, x+2, x+4

ATQ,

(x + 3) ² – (x – 3) ² = 492

⇒ 12x = 492

⇒ x = 41

∴ smallest odd no. = 41 – 4 = 37

S11. Ans.(b)

Sol. Required no. of participants

=24

100× 450 +

20

100× 750 +

15

100× 480 +

15

100× 640 +

5

100× 360= 444

S12. Ans.(c)

Sol. No. of selected participants from Vadodara in 2006

=20

100× 640 = 128

No. of selected participants from Mumbai in 2006

=16

100× 750 = 120

∴ Required percentage =128−120

128× 100

= 6.25% less

Page 5: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

5 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S13. Ans.(d)

Sol. Required average

= 1

5× (

16

100× 450 +

24

100× 750 +

20

100× 480 +

10

100× 640 +

25

100× 360)

=1

5× (72 + 180 + 96 + 64 + 90)

=502

5≈ 100

S14. Ans.(b)

Sol. Selected participants from Lucknow in 2009 & 2010 together

=(25 + 30)

100× 480 = 264

And, that from Bhopal =55

100× 360 = 198

∴ Required ratio =264

198=

4

3 ⇒ 4:3

S15. Ans.(e)

Sol. Required difference

=80

100×

20

100× 450 −

60

100×

16

100× 750 = 72 – 72 = 0

S16. Ans.(d)

Sol.

S17. Ans.(b)

Sol.

S18. Ans.(a)

Sol.

S19. Ans.(c)

Sol.

Page 6: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

6 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S20. Ans.(e)

Sol.

S21. Ans.(a)

Sol. CP of one article =2100

3 = 700

Profit =20

100× 700 = Rs 140

S22. Ans.(b)

Sol. Let investment of A, B and C be x, y and z respectively.

x : y : z = 1440 : 2160 : 2640

x : y : z = 6 : 9 : 11

Required sum (A + B) =15

26× 6500 = Rs 3750

S23. Ans.(d)

Sol. Upstream speed =12

20× 60 = 36 km/hr

Downstream speed =22

22× 60 = 60 𝑘𝑚/ℎ𝑟

x -y = 36 …(i)

x + y = 60 …(ii)

from (i) & (ii)

y = 12 km/hr

S24. Ans.(d)

Sol. Let efficiency of one man and one woman be ‘m’ units/day and ‘w’ units/day respectively.

15m × 12 =18w × 20

1m = 2w

(8m + 12w) ×x = 18w × 20

(16w + 12w) ×x = 18w × 20

𝑥 =18𝑤 × 20

28𝑤 = 12

6

7 days

S25. Ans.(c)

Sol. Principal =𝑆𝐼 × 100

𝑇𝑖𝑚𝑒 × 𝑅𝑎𝑡𝑒

=240 × 100

5 × 6= Rs 800

Page 7: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

7 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

Solutions (26-30):

Total persons who were awarded = 103

20.6× 360 = 1800

States No. of persons who were awarded

UP 542

MP 228

Maharashtra 453

Kerala 103

West Bengal 123

Haryana 351

S26. Ans. (b) Sol. Required answer = 542 + 453 + 123 = 1118 S27. Ans. (c)

Sol. Required parentage = 454–453

453× 100 =

100

453% more

S28. Ans. (d)

Sol. Total Females of MP who were awarded = 1

3 ×228 = 76

Total females of west Bengal who were awarded = 2

3×123 = 82

∴ Required answer = 82−76

82 × 100 ≃ 7.3 % less

S29. Ans. (a)

Sol. Required average = 1

3 × (542 + 228 + 103) = 291

S30. Ans. (b) Sol. Required difference = |(542 + 103 + 123) − (228 + 453 + 351)| = 264 S31. Ans.(d) Sol.

16 ×2.4

100𝑥 = 288

𝑥 = 750 S32. Ans.(b) Sol. (−251 × 21 × (−12))

𝑥=

15813

100

𝑥 = 400 S33. Ans.(d) Sol.

[130 × 130

25× 15]

1

30= 338

Page 8: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

8 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S34. Ans.(e)

Sol.

√√44944 + √52441 = √212 + 229 = √441 = 21

S35. Ans.(d)

Sol. 24.375 − 1.955 = 22.420

S36. Ans.(a)

Sol. 3 Pen + 4 Er + 5 Pa = 28

A → Pa + 0.25 = Pen + Er

B → 10 Pa + 8 Er = 42.5

C→ Pen = 1.8 Er

So, using any two of the 3 statements the cost of Eraser can be determined.

S37. Ans.(c)

Sol. A → 𝑥 + 𝑦 + 𝑥 − 𝑦 = 12, 𝑥 = 6

(𝑥 + 𝑦) − (𝑥 − 𝑦) = 6, 𝑦 = 3

𝑥2: 𝑦2 = 36 ∶ 9 or 4 ∶ 1

B → 𝑦 =𝑥

2, 𝑥2 ∶ 𝑦2 = 4 ∶ 1

C → 𝑦

𝑥=

1

2, 𝑥2: 𝑦2 = 4 ∶ 1

So, anyone of the statements is sufficient to answer the question.

S38. Ans.(e)

Sol. A → 0.82 MP = 516.6, M = 630 Rs.

B → using A, 630 = 1.25 CP, CP = 504 Rs.

C → using A

M = 630, at 10% discount, SP = 567

C.P. =567

112.5= 504 Rs.

So, using either B or C with A we can find the cost price.

S39. Ans.(d)

Sol. Volume of cone = Lateral Surface area 1

3𝜋𝑟2ℎ = 𝜋𝑟ℓ [ℓ = √ℎ2 + 𝑟2]

𝑟ℎ

3= √ℎ2 + 𝑟2

Squaring both sides 1

9=

ℎ2+𝑟2

𝑟2ℎ2

1

9=

ℎ2

𝑟2ℎ2+

𝑟2

𝑟2ℎ2

1

9=

1

𝑟2+

1

ℎ2

Page 9: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

9 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S40. Ans.(a) Sol.

Area = 4 π r2 Cumulative area of the two pieces = 25% more than the by sphere. Area of 2 pieces = 1.25 × 4 π r2 = 5πr2

Extra area = πr2

Extra area = Flat surface area of two new circles that are now created circles.

Area each new circle =𝜋𝑟2

2

Let radius of new circle be r1.

Now, πr12 = 𝜋𝑟2

2

r1 = 𝑟

√2

Now, r1, h and r form a right angled triangle. h2 + r12 = r2

h2 +(𝑟

√2)

2

= r2

h = 𝑟

√2

S41. Ans.(c) Sol. I. 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 II. 3y² + 7y + 4 = 0 ⇒ 3y² + 3y + 4y + 4 = 0 ⇒ (y + 1) (3y + 4) = 0 ⇒ y = –1, –4/3 y ≥ x

Page 10: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

10 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S42. Ans.(e)

Sol. I. 2x² + 21x + 10 = 0

⇒ 2x² + 20 + x + 10 = 0

⇒ (x + 10) (2x + 1) = 0

⇒ x = –10, –1/2

II. 3y² + 13y + 14 = 0

⇒ 3y² + 6y + 7y + 14 = 0

⇒ (y + 2) (3y + 7) = 0

⇒ y = –2, –7/3

No relation

S43. Ans.(e)

Sol. I. 4x² – 13x + 9 = 0

⇒ 4x² – 4x – 9x + 9 = 0

⇒ (x – 1) (4x – 9) = 0

⇒ x = 1, 9/4

II. 3y² – 14y + 16 = 0

⇒ 3y² – 6y – 8y + 16 = 0

⇒ (y – 2) (3y – 8) = 0

⇒ y = 2, 8/3

No relation

S44. Ans.(b)

Sol. I. 8x² + 18x + 9 = 0

⇒ 8x² + 12x + 6x + 9 = 0

⇒ (2x + 3) (4x + 3) = 0

⇒ x = –3/2, –3/4

II. 4y² + 19y + 21 = 0

⇒ 4y² + 12y + 7y + 21 = 0

⇒ (y + 3) (4y + 7) = 0

⇒ x = –3, –7/4

x >y

S45. Ans.(a)

Sol. I. 3x² + 16x + 21 = 0

⇒ 3x² + 9x + 7x + 21 = 0

⇒ (x + 3) (3x + 7) = 0

⇒ x = –3, –7/3

II. 6y² + 17y + 12 = 0

⇒ 6y² + 9y + 8y + 12 = 0

⇒ 3y (2y + 3) + 4 (2y + 3) = 0

⇒ y = – 3/2, –4/3

y > x

Page 11: 1 Adda247 | No. 1 APP for Banking & SSC Preparation Website · 3x² + 10x + 8 = 0 ⇒ 3x² + 6x + 4x + 8 = 0 ⇒ (x + 2) (3x + 4) = 0 ⇒ x = –2, –4/3 . II. 3y² + 7y + 4 = 0

11 Adda247 | No. 1 APP for Banking & SSC Preparation Website: bankersadda.com | sscadda.com | store.adda247.com | Email: [email protected]

S46. Ans.(b)

Sol. Required average

=1

5× (20 + 25 + 35 + 30 + 45)

= 31 thousand

S47. Ans.(c)

Sol. Required difference

|(15 + 20 + 30 + 35 + 40) − (10 + 20 + 25 + 40 + 50)|

= 5000

S48. Ans.(a)

Sol. Required percentage

=35 − 30

35× 100

= 142

7% less

S49. Ans.(d)

Sol. Required ratio =(20 + 35)

(10 + 25)=

11

7

S50. Ans.(a)

Sol. From the graph it is clear that person B gets maximum income in 2005