# 10th Maths Paper Solutions Set 1 : CBSE Abroad Previous Year 2008

General Instructions:
(i) All questions are compulsory.
(ii) The question paper consists of 30 questions divided into four sections A, B, C and D. Section A comprises of 10 questions of one mark each, Section B comprises of 5 questions of two marks each, Section C comprises of 10 questions of three marks each, and Section D comprises of 5 questions of six marks each.
(iii) All questions in section A are to be answered in one word, one sentence or as per the exact requirements of the question.
(iv) Use of calculators is not permitted.
Q1 :

Complete the missing entries in the following factor tree: Let the missing numbers be x and y. From the above factor tree, it is evident that

y= 3 × 7 = 21

x= 2 × y = 2 × 21 = 42

Thus, the factor tree becomes Q2 :

If (x+ a) is a factor of 2x2+ 2ax+ 5x+ 10, then find a.

We divide 2x2+ 2ax+ 5x+ 10 by x+ a Now, it is given that (x+a) is a factor of 2x2+ 2ax+ 5x+ 10. Therefore, the remainder should be zero.

Therefore, we have

10 − 5a= 0

a= 2

Q3 :

Show that x= −3 is a solution of x2+ 6x+ 9 = 0.

We have,

L.H.S. = x2+ 6x+ 9 = (−3)2+ 6 (−3) + 9 ( x= −3)

= 9 − 18 + 9

= 18 − 18

= 0 = R.H.S.

This shows that x= −3 is a solution of x2+ 6x+ 9 = 0

Q4 :

The first term of an A.P. is pand its common difference is q. Find its 10thterm.

Q5 :

If , then find the value of (sin A+ cos A) sec A.

Q6 :

The lengths of the diagonals of a rhombus are 30 cm and 40 cm. Find the side of the rhombus.

Q7 :

In the figure, PQ || BC and AP: PB = 1: 2. Find  Q8 :

The surface area of a sphere is 616 cm2. Find its radius.

Q9 :

A die is thrown once. Find the probability of getting a number less than 3.

Q10 :

Find the class marks of classes 10 − 25 and 35 − 55.

Q11 :

Find all the zeroes of the polynomial x4+ x3− 34x2 − 4x+ 120, if two of its zeroes are 2 and −2.

Q12 :

A pair of dice is thrown once. Find the probability of getting the same number on each die.

Q13 :

If sec 4A= cosec (A− 20°), where 4Ais an acute angle, then find the value of A.

OR

In a ΔABC, right-angled at C, if then find the value of sin Acos B+ cos Asin B.

Q14 :

Find the value of k, if the points (k, 3), (6, −2), and (−3, 4) are collinear.

Q15 :

E is a point on the side AD produced of a ||gm ABCD and BE intersects CD at F. Show that ΔABE ΔCFB.

Q16 :

Use Euclid’s Division Lemma to show that the square of any positive integer is either of the form 3mor (3m+ 1) for some integer m.

Q17 :

Represent the following pair of equations graphically and write the coordinates of points where the lines intersect y-axis:

x+ 3y = 6

2x− 3y= 12

Q18 :

For what value of nare the nthterms of two A.P.’s 63, 65, 67 … and 3, 10, 17 … equal?

OR

If mtimes the mthterm of an A.P. is equal to ntimes its nthterm, then find the (m+ n)thterm of the A.P.

Q19 :

In an A.P., the first term is 8, nthterm is 33, and sum to first nterms is 123. Find nand d, the common difference.

Q20 :

Prove that:

(1+ cot A+ tan A) (sin A− cos A) = sin Atan A− cot Acos A

OR

Without using trigonometric tables, evaluate the following: Q21 :

If P divides the join of A(−2, −2) and B(2, −4) such that , then find the coordinates of P.

Q22 :

The mid-points of the sides of a triangle are (3, 4), (4, 6), and (5, 7). Find the coordinates of the vertices of the triangle.

Q23 :

Draw a right triangle in which the sides containing the right angle are 5 cm and 4 cm. Construct a similar triangle whose sides are times the sides of the above triangle.

Q24 :

Prove that a parallelogram circumscribing a circle is a rhombus.

OR

In figure, AD BC. Prove that AB2+ CD2= BD2+ AC2. Q25 :

In the figure, ABC is a quadrant of a circle of radius 14 cm and a semi-circle is drawn with BC as diameter. Find the area of the shaded region. Q26 :

A peacock is sitting on the top of a pillar, which is 9 m high. From a point 27 m away from the bottom of the pillar, a snake is coming to its hole at the base of the pillar. Seeing the snake, the peacock pounces on it. If their speeds are equal, then at what distance from the hole is the snake caught?

OR

The difference of two numbers is 4. If the difference of their reciprocals is , then find the two numbers.

Q27 :

The angle of elevation of an aeroplane from a point A on the ground is 60°. After a flight of 30 seconds, the angle of elevation changes to 30°. If the plane is flying at a constant height of m, then find the speed, in km/hour, of the plane.

Q28 :

If a line is drawn parallel to one side of a triangle to intersect the other two sides in distinct points, then prove that the other two sides are divided in the same ratio.

Using the above, prove the following:

In figure, AB || DE and BC || EF. Prove that AC || DF. OR

Prove that the lengths of tangents drawn from an external point to a circle are equal.

Using the above, prove the following:

ABC is an isosceles triangle in which AB = AC, circumscribed about a circle, as shown in figure. Prove that the base is bisected by the point of contact. Q29 :

If the radii of the circular ends of a conical bucket, which is 16 cm high, are 20 cm and 8 cm, then find the capacity and total surface area of the bucket. 