Question

Kingsley Matriculation School
Date:21.12.2020 Half Yearly Examination Time: 3 Hrs.
Std:X Maths Marks: 100
I. Choose the correct answer: [ 15x1=15]
1. The first term of an arithmetic progression is unity and the common difference is 4.
Which of the following will be a term of this A.P.
a) 4551 b) 10091 c) 7881 d) 13531
2. An A.P. consists of 31 terms. If its 16th term is m, then the sum of all the terms of this A.P.
Is a) 16 m b) 62 m c) 31m d) 31
2
m
3. If A=265 and B = 264 + 263 + 262+ ……… + 20 which of the following is true?
a) B is 264 more than A b) A and B are equal c) B is larger than A by 1
d) A is larger than B by 1
4. The next term of the sequence 3
16
,
1
8
,
1
12
,
1
18
…… is
a) 1
24
b) 1
27
c) 2
3
d) 1
81
5. The value of (13 + 23 + 33+ ……… + 153
) – (1 + 2 + 3+ ……… + 15) is
a) 14400 b) 14200 c) 14280 d) 14520
6. If (x-6) is the HCF of x
2 – 2x - 24 and x
2 – kx – 6 then the value of k is
a) 3 b) 5 c) 6 d) 8
7. Which of the following should be added to make x
4 + 64 a perfect square.
a) 4 x
2 b) 16 x
2
c) 8 x
2 d) -8 x
2
8. For the given matrix A =[
1 3 5 7
2 4 6 8
9 11 13 15
] the order of the matrix AT is
a) 2x3 b) 3x2 c) 3x4 d) 4x3
9. The values of a and b if 4x4
-24x3+76x2+ax+b is a perfect square are
a) 100, 120 b) 10, 12 c) -120, 100 d) 12, 10
10. Transpose of a column matrix is ----
a) unit matrix b) diagonal matrix c) column matrix d) row matrix
11. The height of a right circular cone whose radius is 5 cm and slant height is 13 cm will be
a) 12 cm b) 10 cm c) 13 cm d) 5 cm
12. If the volume of sphere is 9/16πcu.cm, then its radius is ---
a) 4/3 cm b) ¾ cm c) 3/2 cm d) 2/3 cm
13. If the radius of the base of a cone is tripled and the height is doubled then the volume is –
a) made 6 times b) made 18 times c) made 12 times d) unchanged

Answer 1

Answer:

option 3 is correct

Step-by-step explanation:

Given,  a = 1, d = 4. Option 1 : T = 4551 a + (n-1)d = 4551 1 + (n-1)4 = 4551 n-1=4550/4 = not divisible by  4 Option 2 : T = 10091 n-1 = 10090/4 = not divisible by 4 Option 3 : T=7881 n-1 = 7880/4 = 1970 n = 1971 which is an integer.  Therefore Option 3 is correct.