number system Model Questions & Answers, Practice Test for ssc cgl tier 2

Answer: (b)

Let the number be x.

∵ $x^2 + (56)^2 = 4985$

$x^2$ = 4985 – 3136 = 1849

∴ $x = √{1849}$ = 43

Answer: (d)

The dividend is in the form $a^n – b^n$

Here n is even

⇒ $7^10 – 5^10$ is divisible by both (7 + 5) and (7 – 5)

⇒ $7^10 – 5^10$ is divisible by 12 and 2

Hence, it is divisible by 12 and 2.

No options matching with the given answer.

Answer: (b)

Two prime numbers greater than 2 must be odd.

Sum of two odd numbers must always be even, thus,

X + Y = 87 is not possible.

Answer: (a)

Let Seema's present age be x yeaRs.

Then, Seema's son's present age = $x/4$ years

Seema's father's present age = ${7x}/4$ years.

Then, $x + x/4 + {7x}/4 = 32 × 3$

12x = 96 × 4

$x = {96 × 4}/12 = 32$

∴Required difference = ${7 × 32}/4 - 32/4$

= 56 – 8 = 48 years

Answer: (a)

Sum of 'n odd natural numbers = $n^2$

Sum of odd numbers between 200 + 300

= (1 + 3 + ... + 299) – (1 + 3 + ... 199)

= $(299)^2 – (199)^2$

= (299 + 199) (299 – 199)

= 49800