Number System : Number System
Ques. 1 : Find the greatest four-digit number which is a multiple of 12. : Ques. 1 : Find the greatest four-digit number which is a multiple of 12.
Slide 3 : Answer is 9996
Ques. 2 : Find the smallest 6-digit number which is a multiple of 17. : Ques. 2 : Find the smallest 6-digit number which is a multiple of 17.
Slide 5 : Answer is 100011
Important formulae : Important formulae ?n : n(n+1)/2 Where ?n = Sum of first n natural numbers.
?n ^2: n(n+1)(2n+1)/6 Where ?n^2 = Sum of the squares of first n natural numbers.
?n ^3: [n(n+1)]^2/4 Where ?n^3 = Sum of the cubes of first n natural numbers.
Ques. 4 : Find the sum of first 15 natural no.? : Ques. 4 : Find the sum of first 15 natural no.?
Slide 8 : Answer is 120.
Ques 5 : In a party there are 30 persons present, & everybody shakes hand with all the other persons. What is the total no. of handshakes happening? : Ques 5 : In a party there are 30 persons present, & everybody shakes hand with all the other persons. What is the total no. of handshakes happening?
Slide 10 : Answer is 435
Ques. 6 : The sum of two no. is 28. What could be the max. possible product of those 2 no. ? : Ques. 6 : The sum of two no. is 28. What could be the max. possible product of those 2 no. ?
Slide 12 : Answer is 196.
Ques. 7 : A gardener planted trees exactly in rows & columns, so that no. of rows is 2 more than the no. of columns. If the total of rows & columns is 98, find the no. of trees planted. : Ques. 7 : A gardener planted trees exactly in rows & columns, so that no. of rows is 2 more than the no. of columns. If the total of rows & columns is 98, find the no. of trees planted.
Slide 14 : Answer is 2400.