[B].
[C].
[D].
Answer: Option A
Explanation:
Terms at odd places are 5, 6, 7, 8 etc. and each term at even place is 16.
So, 9 is wrong.
[B].
[C].
[D].
Answer: Option D
Explanation:
(325 + 326 + 327 + 328) = 325 x (1 + 3 + 32 + 33) = 325 x 40
= 324 x 3 x 4 x 10
= (324 x 4 x 30), which is divisible by30.
[B].
[C].
[D].
Answer: Option C
Explanation:
Required length = H.C.F. of 700 cm, 385 cm and 1295 cm = 35 cm.
[B].
[C].
[D].
Answer: Option D
Explanation:
Let C’s age be x years. Then, B’s age = 2x years. A’s age = (2x + 2) years.
(2x + 2) + 2x + x = 27
5x = 25
x = 5.
Hence, B’s age = 2x = 10 years.
[B].
[C].
[D].
Answer: Option D
Explanation:
Sn = (1 + 2 + 3 + … + 50 + 51 + 52 + … + 100) – (1 + 2 + 3 + … + 50)
| = | 100 | x (1 + 100) – | 50 | x (1 + 50) |
| 2 | 2 |
= (50 x 101) – (25 x 51)
= (5050 – 1275)
= 3775.
[B].
[C].
[D].
Answer: Option B
Explanation:
l2 + b2 = 41.
Also, lb = 20.
(l + b)2 = (l2 + b2) + 2lb = 41 + 40 = 81
(l + b) = 9.
Perimeter = 2(l + b) = 18 cm.
[B].
[C].
[D].
Answer: Option A
Explanation:
Each number is twice the preceding one with 1 added or subtracted alternatively.
So, the next number is (2 x 261 + 1) = 523.