Maths For Kids

Question : There are three numbers such that the product of the first two numbers is 91                  and that of the last two numbers is 221. Find all three numbes and their sum Answer : Suppose numbers are A , B AND C. Also given   A x B  = 91 and B x C = 221 Since the numbers are prime number, they contain only 1 as the common factor. Also, above two products have B in common. So, B = H.C.F. of ( 91 and 221 ) = 13; A  = 91/13 = 7;  C  = 221/13 = 17. Required sum = (7 + 13 + 21 ) = 41. ================================================================= Question : The ratio of two numbers is 3 : 4. The L.C.M. of two numbers is 48.                   Find sum of the number Solution : Let the numbers be 3x and 4x. Then, their L.C.M. = 12x. So, 12x = 48 or x = 4 The numbers are 12 and 16. Hence, required sum = (12 + 16) = 28. ===...

Factor :   Factor for a given number are all the numbers which divides given number completely i.e. if you divide given number by factor then there will be no remainder. Question Write all the factors of 100 ? Prime Number : are the numbers which divided completely by only itself or one.               example 2 , 3 , 5 so on Question :   Write all the prime number till 100 ? ========================================================= HCF : Highest common factor of two or more number is the largest number that divide all the number completely    Factor of 10 are 1 ,  2  and 5    Factor of 15 are 1 , 3   and 5  so common factor of 10 and 15 are 1 and 5 in  which 5 is largest so HCF = 5 Note : HCF will be always less than the smallest number or equal to the smallest number.            HCF for prime numbers is 1. i.e there is no common factor other tha...