NCERT Solutions for Class 4th Maths Chapter 13 Making tables by splitting / Multiples of 10 — In-text Questions

Book page 188 Updated on2026-09-19

Q1.
We have seen how to calculate 3 × 14 and 6 × 14 by splitting and doubling. Can we construct the times-14 table by splitting and doubling? Try!
Answer

Yes, we can. Take the times-7 answer and double it every time.

nn × 7double itn × 14
177 + 714
21414 + 1428
32121 + 2142
42828 + 2856
53535 + 3570
64242 + 4284
74949 + 4998
85656 + 56112
96363 + 63126
107070 + 70140
Times-14: 14, 28, 42, 56, 70, 84, 98, 112, 126, 140
Why it happens: 14 is 7 twice. So n fourteens are always n sevens taken twice.
Q2.
What other times-tables can be constructed by splitting into equal groups and doubling? Give examples.
Answer

Any even number can be split into two equal groups.

TableSplit asExample
Times-126 and 68 × 12 = 48 + 48 = 96
Times-168 and 85 × 16 = 40 + 40 = 80
Times-189 and 94 × 18 = 36 + 36 = 72
Times-2010 and 107 × 20 = 70 + 70 = 140

Odd numbers like 15 or 13 cannot be split into two equal whole groups, so we split them as 10 and the rest instead.

Why it happens: Doubling works only when the two groups are exactly the same size.
Q3.
Find the answers to the following: a) 15 × 10 = _____ Tens = _____ b) 16 × 10 = _____ Tens = _____ c) 19 × 10 = _____ Tens = _____ d) 20 × 10 = _____ Tens = _____
Answer
ProblemIn tensAnswer
a) 15 × 1015 Tens150
b) 16 × 1016 Tens160
c) 19 × 1019 Tens190
d) 20 × 1020 Tens200
15 Tens = 10 Tens + 5 Tens = 100 + 50 = 150
20 Tens = 2 Hundreds = 200
Why it happens: Taking a number ten times just turns each one into a ten, so the number of tens is the number itself.
Q4.
10 × 10 = ____ ; 2 times (i.e., double of) 10 × 10 = ____
Answer
10 × 10 = 10 Tens = 100
Double of 100 = 100 + 100 = 200
Two hundred-squares make 200.
Why it happens: Ten tens fill one hundred-square. Two such squares are two hundreds.
Q5.
Discuss in grade what happens when we take several groups of 10.
Answer

Sample answer. Each group of 10 becomes one ten. So the number of groups tells us the number of tens.

Groups of 10TensNumber
6 groups6 Tens60
10 groups10 Tens100
13 groups13 Tens130
25 groups25 Tens250

When we reach 10 tens we bundle them into 1 Hundred, and a new place starts.

Why it happens: Our counting goes in tens. Ten ones make a ten and ten tens make a hundred.
Was this helpful?