How Many Times?Leggy Animals There are 5 goats. How many legs altogether? 4 + 4 + 4 + 4 + 4 = 20 or 5 times 4 is 20 or 5 × 4 = 20 How many spiders? One spider has legs. In all, spider legs are 3 times or + + = or 3 × = Do you know this leggy fellow? This is an octopus. It lives in the sea. It also has 8 legs. So how many legs altogether do 5 octopuses have? + + + + = or 5 times = or 5 × = Give me your hand, hand, hand, .............! Find the Number without Counting How many flowers in a flower bed? It has 4 columns. Each column has 6 flowers. So altogether the flower bed has 4 times 6 flowers, 6 + 6 + 6 + 6 = 24 or 4 × 6 = 24 Let's try another way. The flower bed has 6 rows. Each row has 4 flowers. Altogether the flower bed has 6 times 4 flowers, 4 + 4 + 4 + 4 + 4 + 4 = 24 or 6 × 4 = 24 In the same way, how many bottles are these? times = bottles How many eggs? times = eggs Practice Time A. Rewrite using the + sign. 2 × 5 is 2 times 5 or 5 + 5 4 × 18 is 4 times or + + + 3 × 20 is times or + + 8 × 9 is times or + + + + + + B. Tell how many times! 8 + 8 + 8 = × 8 = 3 + 3 + 3 + 3 + 3 = 5 × = 30 + 30 + 30 = × = 7 + 7 + 7 + 7 + 7 + 7 = × = 12 + 12 + 12 + 12 = × 12 = 6 + 6 + 6 = × = 10 + 10 + 10 + 10 = × = 2 + 2 + 2 + 2 + 2 = × = 6 + 6 + 6 + 6 + 6 + 6 + 6 = × = C. Ramu bought 4 packets of biscuits. Each packet has 4 biscuits. How many biscuits did Ramu buy? D. There are 12 desks in a classroom. Each desk has 4 legs. What is the total number of legs of the desks? E. Sabiha brought home 3 bunches of flowers. Each bunch has 4 flowers. How many flowers were there? F. One rail coach has 8 wheels. How many wheels in all in 6 coaches? Try jumps with seven steps Mithu had some sticks. She arranged them like this: 1 time 5 = 5 2 times 5 = 10 3 times 5 = 15 4 times 5 = 20 Then she counted how many times the sticks were crossing each other. She found that 4 times 5 = 4 × 5 = 20 Let's try making a 2 times table with sticks: 1× 2 = 2 2× 2 = 4 3× 2 = 6 4× 2 = 5× 2 = 6× 2 = 7× 2 = 8× 2 = 9× 2 = 10 × 2 = Now draw sticks to make the multiplication table of 6: Shopping with Tables How much do these things cost? 4 toffees cost rupees. [Hint: 4 × 2] 3 pencil boxes cost rupees. 10 pencil boxes cost rupees. 9 balloons cost rupees. 5 toys cost rupees. 7 face masks cost rupees. Practice Time A. Complete the following: 2 × 7= 3 × 9 = 4 × 9= 5 × 2 = 5 × 8 = 3 × 10= 10 × 6= 2 × 8 = 5 × 9= 10 × 8 = B. Look at the patterns and complete them. 3, 6, 9, , , . 2, 4, 6, , , . 10, 20, 30, , , . 4, 8, 12, , , . 5, 10, 15, , , . 30, 60, 90, , , . C. Complete the multiplication tree D. How many in all? = The almirah has 4 shelves. There are 5 books in each shelf. How many books are in the almirah? 4 × 5 = 20 books = A shirt has 5 buttons. How many buttons would 3 shirts have? = There are four fans. Each fan has 3 blades. What is the total number of blades in all? = A box contains 6 apples. How many apples in all will seven boxes have? = How many corners would 4 triangles have? E. Some multiplication facts: ' 8 × 3 = ' 5 × = 35 ' 3 × = ' × 6 = 36 ' × = 42 ' 10 × = ' 5 × = 40 ' × 9 = 36 ' × = 54 ' × 7 = 28 Multiplying Big Numbers A. Two toffees were given to each student in the class. If there were 34 students, how many toffees were given in all? Total students present = 34 Each student gets 2 toffees. So total number of toffees given is 34 × 2. B. In a picnic 4 fruits were given to every student. The number of students was 23. Find out the total number of fruits given. Number of students in the picnic = 23 Fruits given to each student = 4 Total number of fruits = 23 × 4 20 3 4 Adding 80 and 12 gives 80 + 12 92 So 23 times 4 is 92. Practice Time A.Multiply: ' 22 × 3 = '• 43 × 2 = 21 × 4 = 24 × 2 ='' ' 11 × 5 = ' 30 × 5 = 20 × 4 = 23 × 9 ='' ' 26 × 4 = ' 38 × 2 = 25 × 3 = 24 × 5 ='' ' 35 × 3 = ' 48 × 4 = 32 × 5 = 58 × 2 ='' B.First guess the answer and then calculate: = A flower has five petals. A bunch of flowers has 13 flowers. How many petals are there in the bunch? = A book has 64 pages. What will be the total number of pages in 8 such books? = Students stand in rows in the assembly. There are six rows of students. Each row has 17 students. How many students are there? = A design has 3 flowers in it. A piece of cloth has 17 such designs. How many flowers will be on the cloth? How many in 23 dozen? Many things are sold by the dozen. For example, bangles and bananas are often sold by the dozen. 1 dozen bananas means 12 bananas. So 23 dozen bananas is 23 × 12 bananas. Next Bharti wrote 20 3 10 Write the numbers in the boxes as shown. 10 40 × 10 3 × 10 400 30 40 × 3 3 × 3 120 9 3 Add the numbers in the boxes: 400 120 30 +9 559 So 43 × 13 = 559 Practice Time First guess the answer and then check it by calculating : 42 × 23 = 73 × 11 = 51 × 13 = 54 × 12 = 25 × 36 = 12 × 14 = Multiplication Patterns A. 9×1= 9 9×2= 18 1+8=9 9×3= 27 2+7=9 9×4= 36 3+6=9 9×5= 45 4+5=9 9×= += 9×= += 9×8= += Did you see the pattern in the 9 times table? What numbers are adding up to 9? Observing patterns in multiplication tables deepens the understanding of the number system. B. Complete the grid by multiplying the numbers × 1 2 3 4 5 6 7 8 9 10 1 1 2 3 4 5 6 7 8 9 10 2 2 4 6 8 10 12 14 16 18 20 3 3 6 9 12 15 18 21 24 27 30 4 5 6 7 8 9 10 Look at the cross in your grid. 3 4 6 8 9 Add the numbers together from top to bottom. 3 + 6 + 9 = 18 Add the numbers together from left to right. 4 + 6 + 8 = 18 The total is the same. Look for other such crosses and copy them in your notebook. C. = Mark the numbers 1–10 in the same grid in one colour. = Mark the numbers 12–20 in another colour. = Similarly mark 21–30 in a third colour. Do you see any colour pattern?