Maths Std IV Chapter 7

7. Factors

1. Write properties of
(a) factors  (b) prime numbers   (c) composite number   (d) multiples

2. Fill in the blanks.
(a) The smallest prime number is ________.
(b) A prime number cannot be divided exactly by any other number other than _______
     and itself.
(c) The only even prime number is _______.
(d) ______ and ______ are neither prime nor compostie numbers.
(e) Factorization means writing a number as a ______________ of its factors.
(f) We can write every composite number as a product of factors that are
    ____________ numbers. This is called _____________ factorization.
(g) The biggest factor that is common to all given numbers is called
    ___________________ of the given numbers.
(h) Multiple of a number = __________ x any counting number
(i) The smallest multiple that is common to all given numbers is called the ____________
     of the given numbers.

3. Write two methods of factorization for obtaining prime factors.

4. Write down the factors of the following numbers
    (a) 48    (b) 90

5. Make a factor tree for the following numbers.
    (a) 96    (b) 40

6. Find the common factors of the following numbers.
    (a) 6 and 18      (b) 20, 35 and 60

7. Write the first 100 prime numbers.

8. Write 'true' or 'false'.
    (a) The smallest prime number is 1
    (b) 87 is a prime number
    (c) The smallest factor of every number is 1.

9. Express the following composite numbers as a product of their prime factors.
    Use division method.
    (a) 124   (b) 275

10. Write the difference between multiples and factors.

11. Write the multiples as directed.
(a) First four multiples of 7 _______________.
(b) Fifth multiple of 8 _________________.
(c) Eleventh multiple of 6 _______________.

12. Circle those which are not the multiples of the numbers given in words.
(a) four              8      12      14     16     18     20      22
(b) twelve         26     36       48    17     94     108    121

13. Skip count to complete the following sequence
(a) multiples of 5                   25, 30, 35, _____, _____, _____, _____
(b) multiple of 8                     40, 48, 56, _____, _____, _____, _____
(c) multiples of 13                 26, 39, 52, _____, _____, _____, _____,

14. Find two common multiples of the following numbers.
(a) 5,7        (b) 3, 6, 9

15. Which of the following numbers are divisible by 2?
      (a) 83    (b) 132     (c) 443

16. Which of the following numbers are divisible by 3?
      (a) 317    (b) 442       (c) 906

17. Which of the following numbers are divisible by 5?
      (a) 160    (b) 384    (c) 295

18. Which of the following numbers is divisible by 10?
      (a) 100     (b) 209     (c) 780

19. Find three common multiples of the following numbers.
      (a) 3, 4 and 6      (b) 10, 15 and 20

20. Write first 6 multiples of the following numbers.
      (a) 11    (b) 12

21. Complete the following sequence.
      (a) 18, 22,26, 30, _____, _____, _____,
      (b) 15, 20, _____, _____, _____, 40, _____,

22. Find the following factors.
      (a) Factors of 15 = __________________
           Factors of 36 = __________________
           Common factors of 15 and 36 = __________________

23. Is 246 a multiple of 8?

24. Which of these numbers 84, 215, 306, 825 are divisible by the given numbers?
      (a) 2      (b) 3     (c) 5    (d) 10

25. Express (a) 90    (b) 117 as the product of their prime factors.

26. Write the first five even multiples of 4.

27. Write the first five odd multiples of 11. 

Maths Std IV Chapter 6

6. Division

1. Divide and check your answer.
(a) 2048 by 9   (b) 9023 by 4   (c) 8174 by 31  (d) 9898 by 38

2. Divide using both long and short division method.
(a) 6,873 ÷ 9   (b) 5,486 ÷ 13

3. Divide using cancellation method.
(a) 6,39,000 ÷ 8,000   (b) 7,080 ÷  50

4. Find estimated and actual quotient and remainder of the following. Round off the
    numbers to the nearest 10
(a) 219 ÷ 27   (b) 9,321 ÷ 56

5. Word problems.
(a) Sameer purchased 28 key chains and distributed them equally among 11 friends
     Estimate how many key chains did each friend get.
(b) A baker bakes 876 cookies in a day. He packs them in boxes each of which can
     have 45 cookies. How many boxes will be needed to pack all the cookies?
(c) Frame a word problem for 416 ÷ 13 = ?
(d) A man earns ₹ 12,000 in 10 day. How much will he earn in 18 days?
(e) For school sports day, ₹ 30,000 was collected from 200 students. How much money
     did each student give? If there are 350 students in the school, how much money is
     yet to be collected?

6. Simplify
(a) 3,600 ÷ 90 x 9 + 5 x 24 -120 ÷ 6
(b) 128 ÷ 16 x 5 + 320 x 4 -150 + 280

Maths Std. IV Chapter 5

5. Multiplication

1. Complete the table.

2. Write the properties of multiplication with suitable examples.

3. Circle the correct answer.
(a) 231 x 100 = 2,300;    2,31,000;     23,100;   23,010
(b) 926 x 1,000 = 92,600;   9,26,000;   9,260;    9,20,600

4. Fill in the blanks.
(a) 82 x 3000    (b) 364 x 800

5. Find the product.
(a) 5,203 x 7   (b) 9,806 x 2

6. Multiply using the expanded form and verify the result by actual  multiplication.
(a) 6,153 x 8   (b) 2,956 x 3

7. Find the product.
(a) 149 x 39    (b) 92 x 38   (c) 9,922 x 76   (d) 68 x 137   (e) 8,973 x 602

8. Estimate the product by rounding off to the nearest 10.
(a) 76 x 52   (b) 108 x 175

9. Estimate the product by rounding off to the nearest 100.
(a) 472 x 594   (b) 8,792 x 361

10. Observe the following pattern and complete it.
      1 x 9 + 2                           = 11
      12 x 9 + 3                         = 111
      123 x 9 + 4                       = 1111
      1234 x 9 + ____               = _____________
      123456 x 9 + ____           = _____________
      1234567 x 9 + ____         = _____________

      12345678 x 9 + ____       = _____________

11. Use the simple tricks to find the products.

(a) 8 x 10   (b) 13 x 15   (c) 23 x 25

12. Multiply 526 and 4,615 by 11 using addition.

13. Word problems.

(a) A pet store has 15 tanks of fish. If each tank has 46 fish, how many fish

     does the pet store have?

(b) A company has 1,563 staff workers. There are 80 company vans. If 8 staff

     workers come in each van, how many people come by other means of transport?
(c) A travel agency sold 18 holiday packages for Malaysia and 16 holiday packages
     for Australia. If one holiday package for Malaysia costs Rs. 27,985 and Australia
     Rs. 49,869, how much did the agency earn from the two holiday packages?

(d) Frame two word problems for 3,432 x 6.

14. Simplify 20 x 6 - 16 x 2 + 4 x 5

15. Solve by lattice multiplication.

(a) 145 x 415   (b) 345 x 15

16. Multiply using both lattice and column methods.

(a) 211 x 16   (b) 639 x 705

17. Choose the best estimate and tick the correct answer.
(a) A jewellery company ordered 82 boxes of silver beads. There were 77 beads in each
     box. About how many silver beads did the jewellery company order?
     ____ 64,000                ____ 6,300
(b) A grocery store sold 8 coupons to each house in their locality. There are 639 houses
     in the locality. About how many coupons did the grocery shop distribute in all?
    _____ 5,100                 ____ 5,200