SSC CGL Advance Maths Questions Discussion on WhatsApp Group

Q.1 If r is the remainder when each of 7654,8506, and 9997 is divided by the greatest no d ( d>1) then d-r is equal to ?
A) 14, B)18 ,C) 24 ,D) 28

Q.2 If x⁴+x³+x²+x+1 = 0, then x²⁰¹⁵+x³⁰¹⁵+5
A) 6, B) 7, C) 8, D) -9

Q.3 A vendor purchased 200 mangoes at the rate of Rs 5 per mango. He sold 70 mangoes at a gain of 10%. the percentage of gain at which he must sell the remaining mangoes so as to gain a profit percentage of 20% overall is:
A) 25.4%
B) 23%
C) 22%
D) 22.3%

Q.4 A The number 25⁶⁴×64²⁵ is the square of a natural number n. The sum of digits of n is
A) 7
B) 14
C) 21
D) 28







1. Sol.

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If a number 'a' and a number 'b' are divisible by a number 'n' then, a+b and a-b is also divisible by n

=> let the number be n which divides 7654, 8506 and 9997 leaving a reminder r

=> the required number then becomes H.C.F of 7654-r, 8506-r and 9997-r

=> it could also be the H.C.F of
(8506-r)-(7654-r), (9997-r)-(8506-r) and (9997-r)-(7654-r)

i.e. 852, 1491 and 2343

=> H.C.F of 852, 1491 and 2343 = 213

the required number n is 213.

Dividing numbers 7654, 8506 and 9997 by 213 leaving remainder 199 each.
So (d-r) = 213-199 = 14
Ans: A

2. Sol.

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From the given expression:
x⁴+x³+x²+x+1 = 0 ......i
x⁵+x⁴+x³+x²+x = 0 ......ii
Substract (ii) - (i)
x⁵ = 1
Now
x²⁰¹⁵+x³⁰¹⁵+5
= (x⁵)⁴⁰³+(x⁵)⁶⁰³+5
= 1+1+5
= 7
Ans: B

3. Sol.

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Total gain for 200 mangoes = 200×20% = 40
gain for 70 mangoes = 70×10% = 7
remaining = 40 - 7 = 33
so required percentage for remaining 130 mangoes
= (33/130)×100
= 25.4%
Ans: A

4. Sol.

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n² = 25⁶⁴×64²⁵
n = 5⁶⁴×8²⁵
= 5⁶⁴×2⁷⁵
= (5×2)⁶⁴×2¹¹
= 2048×10⁶⁴
Number n = 204800........0 (Up-to 64 zeros)
Sum of Digits of n = 2+0+4+8 = 14
Ans: B