# S Chand ICSE Mathematics Class 6 Solution First Chapter Numbers Exercise 1B (O.P. Malhotra,  S.K. Gupta, Anubhuti Gangal)

Exercise 1B

(i) In which order should the four different digits be arranged to obtain the largest 4-digit number?

Ans:- Descending

(ii) What is the number of 3-digit number that can be formed using the digits 0, 1 and 5, without repeating a digit in any number?

Ans:- 4

(iii) Write the smallest 3-digit number using the digits 2, 3 and 5.

Ans:- 235

(iv) Write the smallest 4-digit number using the digits 1, 0 and 4. You can repeat any one of the digits twice.

Ans:- 1004

(v) What is the largest 5-digit numbers with 2 at ones place 3 at tens place?

Ans:- 99932

(2) Write all possible 3-digit numbers (without repeating the digits), by using the digits.

(i) 6, 7, 5

Ans:- 567, 576, 657, 756, 765

(ii) 9, 0, 2

Ans:- 209, 290, 902, 920

(3) Use the given digits without repetition and make the smallest and the greatest 4-digit numbers.

(i) 2, 1, 5, 6

Ans:- (i) Greatest = 6521    Smallest = 1256

(ii) 9, 0, 2

Ans:- Greatest = 9870       Smallest = 7089

(4) Make the greatest and the smallest 4-digit numbers by using any one digit twice:

(i) 6, 3, 2

Ans:- Greatest = 6632    Smallest = 2236

(ii) 1, 0, 6

Ans:- Greatest = 6610    Smallest = 1006

(5) Make the greatest and the smallest 4-digit numbers using any four different digits, with the condition given below.

(i) Digit 6 is always in thousands place.

Ans:- Greatest 6987    Smallest  6012

(ii) Digit 4 is always in hundreds place.

Ans:- Greatest 9487    Smallest 1402

(iii) Digit 7 is always in tens place.

Ans:- Greatest 9876    Smallest  1072

(iv) Digit 1 is always in ones place.

Ans:- Greatest 9871      Smallest  2031

(6) How many numbers in all do we have with:

(i) 4 digits

Ans:- 9000

(ii) 6 digits

Ans:- 900000

(7) Write the greatest and the smallest 5-digit numbers using all of the following digits by using any one digit twice.

(i) 6, 3, 8, 2

Ans:- Greatest 88632    Smallest 22368

(ii) 1, 0, 5, 7

Ans:- Greatest 77510    Smallest 10057

(iii) 2, 8, 9, 1

Ans:- Greatest 99821    Smallest 11289

(iv) 5, 7, 0, 3

Ans:- Greatest 77530     Smallest 30057

Multiple Choice Questions (MCQs)

(8) The smallest five digit numbers using two different digits is

(a) 10001   (b) 11110   (c) 10000  (d) 1011

Ans:- (c) 10000

(9) The difference between the greatest five digit number and the greatest five digit number with all different digits is

(a) 1000   (b) 12345    (c) 1     (d) 1234

Ans:- (d) 1234

(10) The sum of the smallest 4-digit number and the greatest 4-digit number using only one digit is

(a) 10999    (b) 10000    (c) 11110      (d) 11011

Ans:- (c) 11110

Challenge!

(11) Take two digits 5 and 7. From them make four-digit numbers, using both the digits equal number of times.

(i) What is the greatest number?

Ans:- 7755

(ii) What is the smallest number?

Ans:- 5577

(iii) What is the number of different numbers that can be formed in all?

Ans:- 6