NCERT Solutions for Class 3 Mathematics Chapter-9 How Many Times?
Find the Number without Counting
1.In the same way, how many bottles are these?
Ans. 4 times 5 = 20 bottles.
2.How many eggs?
Ans. 6 times 5 = 30 eggs.
Practice Time
A.Rewrite using the + sign.
2 x 5 is 2 times 5 or 5 + 5
4 x 18 is 4 times 18 or 18 + 18 + 18 +18
3 x 20 is 3 times 20 or 20 + 20 + 20
8 x 9 is 8 times 9 or 9 + 9 + 9 + 9 +9+9+9+9
B.Tell how many times!
9+9+9+9+9+9=6×9=54
4+4+4+4+4=5×4=20
8 + 8 + 8 = 3×8 = 24
3 + 3 + 3 + 3 + 3 + = 5×3 = 15
30 + 30 + 30 = 3 x 30 = 90
7+7+7+7+7+7=6×7=42
12 + 12 + 12 + 12 = 4 x 12 = 48
6 + 6 + 6 = 3×6 = 18
10 + 10 + 10 + 10 = 40
4 x 10 = 2+2+2+2+2=5×2=10
6+6+6+6+6+6+6=7×6=42
1.Ramu bought 4 packets of biscuits. Each packet has 4 biscuits. How many biscuits did Ramu buy?
Ans. 4 x 4 = 16 biscuits.
2.There are 12 desks in the classroom. Each desk has 4 legs. What is the total number of legs of the desks?
Ans. 12 x 4 = 48 legs.
3. Sahiba brought home 3 bunches of flowers. Each bunch has 4 flowers. How many flowers were there?
Ans. 3 x 4 = 12 flowers.
4.One rail coach has 8 wheels. How many wheels in all in 6 coaches?
Ans. 6 x 8 = 48 wheels.
Stick Play
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 x 5=20
1.Now draw sticks to make the multiplication table of 6:
Ans.1 x 6 = 6
2 x 6 = 12
3 x 6 = 18
4 x 6 = 24
5 x 6 = 30
6 x 6 = 36
7 x 6 = 42
8 x 6 = 48
9 x 6 = 54
10 x 6 = 60
Practice Time
1.Complete the following:
Ans.2×7 = 14 3×9 = 21
5×2=10 5×8 = 40
10×6 = 60 2×8 = 16
10×8 = 80 4×9 = 36 3×10 = 30 5×9 = 45
2.Look at the patterns and complete them.
Ans.3, 6, 9, 12,15, 18
2, 4, 6, 8, 10,12
10, 20, 30,40, 50,60
4, 8, 12,16,20, 24
5, 10,15,20, 25,30
30,60,90,120,150, 180
3.Complete the multiplication tree.
Ans.
4.How many in all?
(i)The almirah has 4 shelves. There are 5 books in each shelf. How many books are in the almirah?
Ans. 4 x 5 = 20 books.
(ii)A shirt has 5 buttons. How many buttons would 3 shirts have?
Ans. 5 x 3 = 15 buttons.
(iii)There are 4 fans. Each fan has 3 blades. What is the total number of blades in all?
Ans. 4 x 3 = 12 blades.
(iv)A box contains 6 apples. How many apples in all will seven boxes have?
Ans. 6 x 7 = 42 apples.
(v)How many corners would 4 triangles have?
Ans. 4 x 3 = 12 corners.
5.Some Multiplication Facts
Ans.(i)8 x 3 = 24 (ii) 5 x 7 = 35 , (iii) 3 x 4 = 12
Multiplying Big Numbers
1.Two toffees were given to each student in the class. If there were 34 students, how many toffees were given in all?
Ans. Total number of students = 34 Each student gets 2 toffees.
So, total number of toffees = 34 x 2
So, 34 times 2 is 68.
2.In a picnic 4 fruits were given to every student. The number of students was 23. Find out the total number of fruits given.
Ans. Number of students in the picnic = 23
Number of fruits given to each student = 4
Total number of fruits = 23 x 4
So, 23 times 4 is 92.
Practice Time
1.Multiply:
(i) 22×3 =——— (ii) 43×2 = ——— (iii) 21×4 =———
(iv) 24 x 2 =——— (v) 11×5 =——— (vi) 30 x 5 =———
(vii) 20 x 4 =——— (viii) 23 x 9 =——— (ix) 26 x 4 =———
(x) 38 x 2 =——— (xi) 25 x 3 =——— (xii) 24 x 5 =———
(xiii) 35 x 3 =——— (xiv) 48 x 4 =——— (xv) 32 x 5 =———
(xvi) 58 x2 =———
Ans. (i) 22 x 3 = 20 x 3 + 2 x 3 =60 + 6= 66
(ii)43×2 = 40×2 + 3×2 =80 + 6= 86
(iii)21 x 4 = 20 x 4 + 1 x 4 = 80 + 4 = 84
(iv)24 x 2 = 20 x 2 + 4 x 2 = 40 + 8 = 48 ”
(v)11 x 5 = 10 x 5 + 1 x 5 = 50 + 5 = 55
(vi)30 x5 = 150
(vii) 20 x4 = 80
(viii)23×9 = 20×9 + 3×9 = 180 + 27 = 207
(ix)26 x 4 = 20 x 4 + 6 x 4 = 80 + 24 = 104
(x)38 x 2 = 30 x 2 + 8 x 2 = 60 + 16 = 76
(xi)25 x 3 = 20 x 3 + 5 x 3 = 60 + 15 = 75
(xii)24 x 5 = 20 x 5 + 4 x 5 = 100 + 20 = 120
(xiii)35×3 = 30×3 + 5×3 = 90 + 15 = 105
(xiv)48 x 4 = 40 x 4 + 8 x 4 = 160 + 32 = 192
(xv) 32 x 5 = 30 x 5 + 2 x 5 = 150 + 10 = 160
(xvi)58 x 2 = 50 x 2 + 8 x 2 = 100 + 16 = 116.
2.First guess the answer and then calculate:
(i)A flower has five petals. A bunch of flowers has 13 flowers. How many petals are there in a bunch?
Ans. Guess: 13 is more than 10 and less than 20 10 times 5 is 50 20 times 5 is 100
So, 13 times 5 is between 50 and 100
Calculation:13 x 5=10×5+3×5
=50+15=65
Hence, there are 65 petals in the bunch.
(ii)A book has 64 pages. What will be the total number of pages in 8 such books?
Ans. Guess: 64 is more than 60 and less than 70 60 times 8 is 480 70 times 8 is 560
So, 64 times 8 is between 480 and 560 Calculation:
64 x 8
= 60×8 + 4×8 = 480 + 32 = 512
Hence, there are 512 pages in 8 books.
(iii) Students stand in rows in the assembly. There are six rows of students. Each row has 17 students. How many students are there?
Ans. Guess: 17 is more than 10 and less than 20 10 times 6 is 60 20 times 6 is 120
So, 17 times 6 between 60 and 120
Calculation: ”
17×6
= 10×6 + 7×6 = 60 + 42 = 102
Hence, there are 102 students in 6 rows.
(iv) A design has 3 flowers in it. A piece of cloth has 17 such designs. How many flowers will be on the cloth?
Ans. Guess: 17 is more than 10 and less than 20 10 times 3 is 30 20 times 3 is 60
So, 17 times 3 is between 30 and 60 Calculation:
17 x 3
= 10×3 + 7×3 = 30 + 21 = 51.
Multiplication Patterns
9×1 = 9
9 x 2 = 18 1 + 8 = 9
9 x 3 = 27 2 + 7 = 9
9 x 4 = 36 3 + 6 = 9
9 x 5 = 45 4 + 5 = 9
9 x 6 = 54 5 + 4 = 9
9 x 1 = 63 6 + 3 = 9
9 x 8 = 12 1 + 2 = 9
1.Did you see the pattern in the 9 times table? What numbers are adding up to 9?
Ans. The 9 times table shows a certain pattern. Digit sum of the products is always
2.Complete the grid by multiplying the numbers.
Look at the cross in your grid.
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.
Ans. The complete grid is as follows:
Let us add numbers as follows:
6 + 12 + 18 = 36 10 + 12 + 14 = 36 9 + 18 + 27 = 54 16 + 18 + 20 = 54 8 + 10 + 12 = 30 5 + 10 + 15 = 30
In each crosses the total remains the same.
•Mark the numbers 1 – 10 in the same grid in one colour. •’ Mark the numbers 12 – 20 in another colour.
• imilarly, mark 21 – 30 in a third colour.