numbers

How many 4 digit nos.are there that is divisible by 29 and the sum of digits are equal to 29.

position in class - STD VI

If in a class of 37 students the place of Nanu and Bhanu are 10th and 16th respectively, what
are their places from the last?

A. 27th and 22nd        B. 28th and 20th      C. 27th and 21st       D. 28th and 22nd

Singapore maths Olympiad

Let a,b,c,d be real numbers such that a² + b² + 2a – 4b + 4 = 0 and c² + d² – 4c + 4d + 4 = 0.

Let m and M be minimum and Maximum value of (a – c)² + (b – d)² respectively. What is m x M.

Singapore maths olympiad, number

If a₁, a₂, a₃, .............. a₂₀₁₁ are positive integers such that (a₁ + a₂ + .....a₂₀₁₁) = a₁.a₂.....a₂₀₁₁

Then find the max value of (a₁ + a₂ + .....a₂₀₁₁)

Singapore maths Olympiad

Find the largest positive integer ‘n’ such that (n + 10) is a divisor of n³ + 2011

Singapore maths Olympiad, Numbers

Let 'n' be the smallest positive integer such that the sum of its digits is 2011. how many digits does 'n' have?

Singapore maths Olympiad

If x = 10000..................................0001000.............................00050
                      2011 times                              2012 times

Which of the following is a perfect square?

a) x - 75  b) x - 25   c) x + 25    d) x + 75

algebra

Find the value of: (64 - 12)2 + 4 x 64 x 12 = ?
A. 5246	B. 4406
C. 5126	D. 5776

divisibility

How many 3 digit numbers are completely divisible 6 ?
A. 146	B. 148
C. 150	D. 152

Numbers

Find 4 consecutive prime numbers that add up-to 220.

fun with numbers

Remembering Ramanujam

1 x 9 + 2 = 11
12 x 9 + 3 = 111
123 x 9 + 4 = 1111
1234 x 9 + 5 = 11111
12345 x 9 + 6 = 111111
123456 x 9 + 7 = 1111111
1234567 x 9 + 8 = 11111111
12345678 x 9 + 9 = 111111111
123456789 x 9 + 10 = 1111111111

fun with numbers

Remembering Ramanujam

more with numbers

9 x 9 + 7 = 88
98 x 9 + 6 = 888
987 x 9 + 5 = 8888
9876 x 9 + 4 = 88888
98765 x 9 + 3 = 888888
987654 x 9 + 2 = 8888888
9876543 x 9 + 1 = 88888888
98765432 x 9 + 0 = 888888888

fun with numbers

Remembering Ramanujam

more on interesting numbers

1 x 1 = 1
11 x 11 = 121
111 x 111 = 12321
1111 x 1111 = 1234321
11111 x 11111 = 123454321
111111 x 111111 = 12345654321
1111111 x 1111111 = 1234567654321

numbers

Remembering Ramanujam
Fun with numbers --- note the symmetry
1 x 9 + 2 = 11
12 x 9 + 3 = 121
123 x 9 + 3 = 12321
1234 x 9 + 4 = 1234321
12345 x 9 + 5 = 123454321
123456 x 9 + 6 = 12345654321
1234567 x 9 + 7 = 1234567654321
12345678 x 9 + 8 = 123456787654321
123456789 x 9 + 9 = 12345678987654321

numbers

10th was the BD of Ramanujam

to remember him here is some interesting symmetry in numbers

1 x 8 + 1 = 9
12 x 8 + 2 = 98
123 x 8 + 3 = 987
1234 x 8 + 4 = 9876
12345 x 8 + 5 = 98765
123456 x 8 + 6 = 987654
1234567 x 8 + 7 = 9876543
12345678 x 8 + 8 = 98765432
123456789 x 8 + 9 = 987654321 

numbers

The number 142857 has the remarkable property that multiplying it by 1, 2, 3, 4, 5, and 6 cyclically permutes the digits.

142857 x 1 = 142857
142857 x 2 = 285714
142857 x 3 = 428571
142857 x 4 = 571428
142857 x 5 = 714285
142857 x 6 = 857142

can you think of any other number?

JMO - application of addition, subtraction and multiplication

Your are given that 12345 x 33 = 407385
Use this information, and the concept of addition, subtraction, multiplication and division to arrive at the multiplication of 12345 x 336567.
You cannot  multiply directly.

factors and number

If the sum of the factors of a number is 124. What is the number?

JMO, numbers

divisibility, numbers

Let n be the total number of different 5 digit numbers that are divisible by 4. The digits comprise of 1, 2, 3, 4, 5 and 6. No digit is repeated in a number. What is the value of n?