NCERT Solutions for Class 4th Maths Chapter 9 The multiplication chart — In-text Questions
Book page 135 Updated on2026-09-19
Q1.
Fill each square in the chart by multiplying the row number by the column number.The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
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The blank chart printed in the book.
Multiply the row number by the column number for every square.
Tip: Fill a whole row by skip counting. Row 6 is 6, 12, 18, 24, 30, 36, 42, 48, 54, 60.
Q2.
What do you notice about the numbers shaded in green? Why is this happening?The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
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56
63
70
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48
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80
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The chart with the green squares marked in orange.
The green numbers come in matching pairs, one on each side of the diagonal line.
One square
Its partner
Number
1 × 2
2 × 1
2
2 × 3
3 × 2
6
2 × 5
5 × 2
10
3 × 8
8 × 3
24
4 × 10
10 × 4
40
Each green pair gives the same product.
Why it happens: 3 rows of 8 dots and 8 rows of 3 dots are the same dots, just turned around. So 3 × 8 and 8 × 3 must both be 24.
Q3.
Share the patterns that you notice in the table.The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
×
1
2
3
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9
10
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1
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6
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8
9
10
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20
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36
40
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5
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35
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6
12
18
24
30
36
42
48
54
60
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7
14
21
28
35
42
49
56
63
70
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8
16
24
32
40
48
56
64
72
80
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9
18
27
36
45
54
63
72
81
90
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The completed multiplication chart.
Here are some patterns we can see.
Every row is a skip-counting list. Row 4 goes 4, 8, 12, 16, … , adding 4 each time.
Row 10 ends in 0 every time: 10, 20, 30, … , 100.
Row 5 ends in 5, 0, 5, 0, 5, 0 …
The chart is the same on both sides of the corner-to-corner line.
The numbers 1, 4, 9, 16, 25, 36, 49, 64, 81, 100 sit on that line.
Row 9 numbers have digits that add to 9: 18 → 1 + 8 = 9, 27 → 2 + 7 = 9.
Try this: Cover a row, skip count aloud, then check the chart.
Q4.
Are the numbers in row 7 the same as the numbers in column 7? In general, are the numbers in a given row the same as the numbers in the corresponding column? Why does this happen?The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
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1
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1
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8
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24
28
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36
40
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5
10
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25
30
35
40
45
50
6
6
12
18
24
30
36
42
48
54
60
7
7
14
21
28
35
42
49
56
63
70
8
8
16
24
32
40
48
56
64
72
80
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9
18
27
36
45
54
63
72
81
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Row 7 and column 7 of the chart.
Yes. Row 7 and column 7 hold exactly the same numbers.
This happens for every row and its matching column.
Why it happens: Row 7 column 3 means 7 × 3 and row 3 column 7 means 3 × 7. Turning an array of dots sideways does not change how many dots there are, so both are 21.
Q5.
Is there a row where all answers (products) are even numbers? Which rows have this property?The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
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1
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1
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5
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35
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6
12
18
24
30
36
42
48
54
60
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7
14
21
28
35
42
49
56
63
70
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8
16
24
32
40
48
56
64
72
80
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18
27
36
45
54
63
72
81
90
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100
The completed multiplication chart.
Yes. Rows 2, 4, 6, 8 and 10 have only even products.
Row 2: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20 — all even Row 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60 — all even
Why it happens: These are the even rows. An even number of things can always be shared into two equal groups, and taking many copies of it keeps it even.
Q6.
Is there a row having only odd numbers as products?The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Why it happens: Every row has a column 2, a column 4 and so on. Any number multiplied by an even number gives an even answer, so no row can be all odd.
Q7.
Are there rows that have both even and odd numbers? What do you notice? Why is it so?The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
×
1
2
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4
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1
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36
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5
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35
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6
12
18
24
30
36
42
48
54
60
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7
14
21
28
35
42
49
56
63
70
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8
16
24
32
40
48
56
64
72
80
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9
18
27
36
45
54
63
72
81
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The completed multiplication chart.
Yes. Rows 1, 3, 5, 7 and 9 — the odd rows — have both even and odd numbers.
Row 3: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30 odd, even, odd, even, odd, even … the two keep taking turns.
Why it happens: An odd number times an odd number stays odd, but an odd number times an even number becomes even. The columns go odd, even, odd, even, so the answers do too.
Q8.
Are there more even numbers in the chart or odd numbers? How do you know?The multiplication chart from the book: 10 rows and 10 columns, with the green squares and the diagonal line marked.
Answer
×
1
2
3
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10
1
1
2
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5
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30
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6
6
12
18
24
30
36
42
48
54
60
7
7
14
21
28
35
42
49
56
63
70
8
8
16
24
32
40
48
56
64
72
80
9
9
18
27
36
45
54
63
72
81
90
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10
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30
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100
The completed multiplication chart.
There are many more even numbers.
Rows 2, 4, 6, 8, 10 are fully even → 5 × 10 = 50 even numbers Rows 1, 3, 5, 7, 9 have 5 even numbers each → 5 × 5 = 25 even numbers Even numbers in all = 50 + 25 = 75 Odd numbers in all = 100 − 75 = 25
Why it happens: A product is odd only when both the row and the column are odd. That happens in just 25 of the 100 squares.