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5. Write the predecessor and successor of the given numbers.

Predecessor Number Successor

(a) _______________ 889 _______________

(b) _______________ 2341 _______________

(c) _______________ 7038 _______________

(d) _______________ 9000 _______________

6. Choose and write the largest number from the given numbers.

(a) 3124, 2689, 708, 4925, 4259

(b) 1987, 2000, 2999, 2001, 399

(c) 6023, 6203, 6302, 6320, 6032

(d) 9989, 9819, 9899, 9879, 9897

Forming 4-Digit Numbers

We can form numbers using the given digits by arranging them in different order.

• To form the greatest 4-digit number, arrange the given digits in descending
order.

• To form the smallest 4-digit number, arrange the given digits in ascending order.

Example 3: Write the greatest and the smallest 4-digit numbers using the digits 2, 9, 0
and 5.

Solution: The greatest 4-digit number is 9520.

(on arranging the digits in descending order)
The smallest 4-digit number is 2059.

(on arranging the digits in ascending order)

Quick Tip

Note that the smallest 4-digit number is 2059 and not 0259 as 0 in the beginning of a
number has no value. So to form the smallest 4-digit number, place 0 at the hundreds place.

Skip Counting

You have already learnt skip counting in 2s, 3s, 5s and 10s in the previous class. Now
let’s learn skip counting in 100s and 1000s.

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