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Page No 1:

Question 1:

Write the following numbers in words.

(a) 3,81,742

(b) 7,80,65,043

 

Answer:

(a) Three lakhs eighty-one thousand seven hundred and forty-two

(b) Seven crores eighty lakhs sixty-five thousand and forty-three

Page No 1:

Question 2:

Write the numbers using comma in International system.

(a) 804321

(b) 9705064

Answer:

(a) 804,321

(b) 9,705,064

Page No 1:

Question 3:

Write the numerals for the following

(a) Forty six lakh, five thousands, seven hundred and ninety

(b) Fifty three crore, four lakh, three thousand and eight.

Answer:

(a) 46,05,790

(b) 53,04,03,008

Page No 1:

Question 4:

Express the following in powers of 10.

(a) 6,54,320

(b) 76,40,321

 

Answer:

(a)

(b)

Page No 1:

Question 5:

Express the following standard form.

(a) 5 × 106 + 4 × 105 + 2 × 103 + 9 × 102 + 6 × 100

(b) 4 × 105 + 8 ×103 + 7 × 101

Answer:

(a) 54, 02, 906

(b) 4,08,070

Page No 1:

Question 6:

Express the following numbers in Roman number system.

(a) 46

(b) 564

(c) 1,257

Answer:

(a) 46 = 40 + 6 = XL + VI = XLVI

(b) 564 = 500 + 60 + 4 = D + LX + IV = DLXIV

(c) 1257 = 1000 + 200 + 50 + 7 = M + CC + L + VII = MCCLVII

Page No 1:

Question 7:

Convert the following numbers into base 5 system.

(a) 19

(b) 37

(c) 48

Answer:

(a)

(b)

(c)

Page No 1:

Question 8:

Convert the Base 5 numerals into Base 10.

(a) 41(5)

(b) 132(5)

(c) 204(5)

 

Answer:

(a)

(b)

(c)

Page No 1:

Question 9:

Express the following in exponential form.

(a) 3 × 3 × 3 × 3

(b) 5 × 5 × 5

Answer:

(a)

(b)

Page No 1:

Question 10:

Expand the following exponents.

(a) 24

(b) 42

(c) 65

Answer:

(a)

(b)

(c)

Page No 1:

Question 11:

Find the value of

(a) 52

(b) 34

 

Answer:

(a)

(b)



Page No 2:

Question 12:

Simplify:

(a) 6,048 + 36 + 8 + 769

(b) 4,670 − 3,294

(c) 6,847 + 3,521 − 4,053 − 3,082

(d) 5,609 × 84

(e) 4,536 ÷ 42

 

Answer:

(a)

(b)

(c)

(d)

(e)

Page No 2:

Question 13:

Group the following numbers which are divisible by 3, 4 and 5

296, 312, 145, 720, 48, 375, 600

 

Answer:

A given number is divisible by 3 if the sum of all the digits is divisible by 3.

A given number is divisible by 4 if the number formed by the last two digits is divisible by 4.

A given number is divisible by 5 if it ends with 0 or 5.

The numbers divisible by 3 are 312, 720, 48, 375, and 600.

The numbers divisible by 4 are 296, 312, 720, 48, and 600.

The numbers divisible by 5 are 145, 720, 375, and 600.

Page No 2:

Question 14:

Write all the factors of

(a) 68

(b) 125

Answer:

(a) 1, 2, 4, 17, 34, 68

(b) 1, 5, 25, 125

Page No 2:

Question 15:

Find the H.C.F of

(a) 45, 60

(b) 54, 27

 

Answer:

(a) H.C.F. = 15

(b) H.C.F. = 27

Page No 2:

Question 16:

Find the L.C.M. of

(a) 10, 12

(b) 30, 46

 

Answer:

(a) L.C.M. = 60

(b) L.C.M. = 690

Page No 2:

Question 17:

Write next three equivalent fractions of

(a)

(b)

 

Answer:

(a)

The next three equivalent fractions of are, and.

(b)

The next three equivalent fractions of are, and.

Page No 2:

Question 18:

Reduce the following to their lowest terms.

(a)

(b)

(c)

 

Answer:

(a)

(b)

(c)

Page No 2:

Question 19:

Simplify the following

(a) 12 + [{1 + (15 − 3)} × 4]

(b)

(c)

(d)

(e)

Answer:

(a)

(b)

(c)

(d)

(e)



Page No 3:

Question 20:

Simplify the following

(a) 9.52 + 0.082 + 3.4156

(b) 7.35 − 1.026

Answer:

(a)

(b)

Page No 3:

Question 21:

Nandini scored 552 marks out of 600 in the 7th standard annual examination. Find the percentage of marks scored by her.

Answer:

Percentage of marks scored by Nandini

Page No 3:

Question 22:

Gowtham bought a bicycle for Rs 2,700. If the marked price of the bicycle is Rs 3,000, find the rate of discount.

 

Answer:

Cost price = Rs.2,700

Marked price = Rs.3,000

Rate of discount

Page No 3:

Question 23:

Hussain bought a television set for Rs 15,000. After some days he sold it for Rs 12,000. Find the percentage of loss.

 

Answer:

Cost price = Rs.15,000

Selling price = Rs.12,000

Loss percentage

Page No 3:

Question 24:

Sophia deposited Rs 8,000 in a post office for 5 years at the rate of 9% p.a. simple interest. Find the interest earned.

 

Answer:

Principal = Rs.8,000

Time= 5 years

Rate = 9% p.a.

Simple Interest

Page No 3:

Question 25:

Somappa and Hanumappa started a partnership business investing Rs 24,000 and Rs 32,000 respectively. Find the ratio of their investments.

 

Answer:

Ratio of their investments

Page No 3:

Question 26:

Find the value of x in each of the following:

(a) x : 3 :: 15 : 5

(b) 10 : x :: 2 : 3

Answer:

(a)

(b)

Page No 3:

Question 27:

(a) Write the set in Roster method. X = {months in a year}

(b) Write the set in Rule method. Y = {1, 4, 9, 16, 25}

Answer:

(a)

(b)

Page No 3:

Question 28:

Write the equivalent and the equal symbol for the following sets.

 

Answer:

(a) Equivalent AB

(b) Equal P = Q

Page No 3:

Question 29:

Classify the following as finite, infinite or null sets.

(a) Set of odd numbers

(b) Set of persons living for three hundred years

(c) Set of letters in the word ‘TEACHER’

Answer:

(a) Infinite set

(b) Null set

(c) Finite set

Page No 3:

Question 30:

Classify the following into monomial, binomial and trinomial expression.

(a) 5abc

(b) xy + z

(c) ab + bc

(d) ab × d

(e) 5x + 1

(f) 6m + 7n − 10

Answer:

(a) Monomial

(b) Trinomial

(c) Binomial

(d) Monomial

(e) Binomial

(f) Trinomial



Page No 4:

Question 31:

Add the following

(a) 2m, 6m, m

(b) 2pq, 4pq, 8pq, pq

(c) 7x, 4y, 3x, 2y

(d) 8xyz, 12yzx

(e) 4ab, 5bc

 

Answer:

(a)

(b)

(c)

(d)

(e)

Page No 4:

Question 32:

Subtract:

(a) 4ax from 8ax

(b) 7pqr from 12 pqr

 

Answer:

(a)

(b)

Page No 4:

Question 33:

Find the product of

(a) 6a × 4a

(b) 5x × 7y

(c) 4m2n × 6mn

(d) 3p × 2q × 2r

(e) 5x2y × 4x3y2 × 2z

Answer:

(a)

(b)

(c)

(d)

(e)

Page No 4:

Question 34:

Divide:

(a) 10a2b ÷ 5ab

(b) 18x3y2 ÷ 6x2y2

 

Answer:

(a)

(b)

Page No 4:

Question 35:

(a) (m × 4m) − (3m4 ÷ m2)

(b) (x5 ÷ x3) + 3x2

 

Answer:

(a)

(b)

Page No 4:

Question 36:

Solve the following

(a) P + 4 = 15

(b) m − 9 = 4

(c) x + 2x + 1 = 4x + 6

(d) 9a − 3a − 4a − 6 = 0

Answer:

(a)

(b)

(c)

(d)

Page No 4:

Question 37:

What is the frequency denoted by these tallies.

(a)

(b)

(c)

(d)

 

Answer:

(a) 5

(b) 6

(c) 13

(d) 17



Page No 5:

Question 38:

Find the Range of the following scores.

(a) 18, 23, 19, 25, 22, 14, 21, 30

(b) 45, 39, 40, 36, 42, 48, 39

Answer:

(a) Range = Highest number − Lowest number = 30 − 14 = 16

(b) Range = Highest number − Lowest number = 48 − 36 = 12

Page No 5:

Question 39:

Find the size of the class interval in the following:

(a) 11 − 20

(b) 31 − 35

(c) 41 − 49

Answer:

(a) Size of the class interval = (20 11) + 1 = 10

(b) Size of the class interval = (35 31) + 1 = 5

(c) Size of the class interval = (49 − 41) + 1 = 9

Page No 5:

Question 40:

Prepare a frequency distribution table for the following scores. (size of the CI is 5)

14

19

24

35

16

11

18

25

29

19

21

23

29

33

Answer:

Class Interval (C.I)

Frequency

(f)

10 − 15

2

15 − 20

4

20 − 25

3

25 − 30

3

30 − 35

2

Page No 5:

Question 41:

(a) Write the complementary angle of 20°

(b) Write the supplementary angle of 108°

Answer:

(a) Complementary angle of

(b) Supplementary angle of

Page No 5:

Question 42:

Find the remaining angles in the following figure.

(a)

(b)

(c)

(d)

 

Answer:

(a)

(b)

(c)

(d)

Page No 5:

Question 43:

Draw a line AB = 5.5 cm. Mark a point X and construct an angle of 60° by using compass at X.

 

Answer:

Page No 5:

Question 44:

Construct a triangle PQR in which PQ = 6.4 cm, PR = QR = 5 cm

Answer:

Construction of triangle PQR:

(i) Draw a line segment PQ of length 6.4 cm.

(ii) With P as centre, draw an arc of radius 5 cm.

(iii) With Q as centre, draw another arc of radius 5 cm.

(iv) The two arcs intersect at a point R.

(v) Join PR and QR.

Page No 5:

Question 45:

Construct the triangle MNO, NO = 4.8 cm, and measure the two sides of the triangle.

Answer:

Construction of triangle MNO:

(i) Draw a line segment NO of length 4.8 cm.

(ii) With N as centre, draw , using compass.

(iii) With O as centre, draw , using compass.

(iv) Mark the intersection of the two sides of the triangle as M.

By measuring, we get

cm and cm.



Page No 6:

Question 46:

Observe the figure and fill in the blanks:

(a) ‘O’ = ……….

(b) OA = ……….

(c) BOC = ……..

(d) DE = ……….

Answer:

(1) ‘O’= Centre of the circle

(2) OA = Radius

(3) BOC= Diameter

(4) DE = Chord

Page No 6:

Question 47:

Write the two properties of the following quadrilaterals.

(a) rectangle

(b) trapezium

(c) rhombus

Answer:

(a) Properties of a rectangle:

(i) Opposite sides of a rectangle are parallel and equal.

(ii) Each angle of a rectangle is a right angle.

(b) Properties of a trapezium:

(i) At least one pair of opposite sides is parallel.

(ii) The sum of all the angles of a trapezium is .

(c) Properties of a rhombus:

(i) The adjacent sides of a rhombus are equal.

(ii) The diagonals of a rhombus bisect each other.

Page No 6:

Question 48:

Find the sum of the interior angles of the followings:

(a) triangle

(b) quadrilateral

Answer:

(a)

(b)

Page No 6:

Question 49:

Name of the following polygons.

(a) 8 sided polygon

(b) 7 sided polygon

Answer:

(a) Octagon

(b) Heptagon

Page No 6:

Question 50:

Write the formula to find the area of:

(a) a triangle

(b) a rectangle

Answer:

(a) Area of a triangle

(b) Area of a rectangle



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