Page 94 - MathGenius-C1-Flipbook

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\ 04-Oct-2025 Bharat Arora Proof-8 Reader’s Sign _______________________ Date __________

BIGGER NUMBERS oN AN ABACUS

We know that a two-spiked abacus is used to A spike cannot have

represent a 2-digit number. more than 9 beads.
Let us show the number 59 on the abacus.
It has 5 tens and 9 ones. t O

So, we put 9 beads on the ones spike and 5 beads 5 9
on the tens spike as shown.

WhAT CoMES AfTER, BEfoRE oR BETWEEN

Look at the table below.

Before Between After
The number that The number in The number that
comes just before is between is one less comes just after is

always 1 less than the than the next number always 1 more than the
given number. and one more than the given number.

previous number.
65 –1 66 +1 67

Look at the number line.
Before After

64 65 66 67 68 69 70
Between
65 comes just before 66 (65 is 1 less than 66).

67 comes just after 66 (67 is 1 more than 66). Challenge Question

So, 66 lies between 65 and 67. Identify the number that comes
between 70 and 68.

Think Tank #Logical Thinking
What number between 60 to 69 has a digit in the ones place that is 1 more than the digit in the tens place?
Tens Ones

Also, write the numbers between which the above number lies.

Teacher’s Using a tailor/number tape, explain what comes just before, just after a number or what comes between two
Tip numbers.

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