find the H. C. F and l. c. m of the number 15,19,and25
Answers
Answer:
Step-by-step explanation:
The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 15 and 19, than apply into the LCM equation.
GCF(15,19) = 1
LCM(15,19) = ( 15 × 19) / 1
LCM(15,19) = 285 / 1
LCM(15,19) = 285
Least Common Multiple (LCM) of 15 and 19 with Primes
Least common multiple can be found by multiplying the highest exponent prime factors of 15 and 19. First we will calculate the prime factors of 15 and 19.
Prime Factorization of 15
Prime factors of 15 are 3, 5. Prime factorization of 15 in exponential form is:
15 = 31 × 51
Prime Factorization of 19
Prime factors of 19 are 19. Prime factorization of 19 in exponential form is:
19 = 191
Now multiplying the highest exponent prime factors to calculate the LCM of 15 and 19.
LCM(15,19) = 31 × 51 × 191
LCM(15,19) = 285
answer
We will learn the relationship between H.C.F. and L.C.M. of two numbers.
First we need to find the highest common factor (H.C.F.) of 15 and 18 which is 3.
Then we need to find the lowest common multiple (L.C.M.) of 15 and 18 which is 90.
H.C.F. × L.C.M. = 3 × 90 = 270
Also the product of numbers = 15 × 18 = 270
Therefore, product of H.C.F. and L.C.M. of 15 and 18 = product of 15 and 18.
Again, let us consider the two numbers 16 and 24
Prime factors of 16 and 24 are:
16 = 2 × 2 × 2 × 2
24 = 2 × 2 × 2 × 3
L.C.M. of 16 and 24 is 48;
H.C.F. of 16 and 24 is 8;
L.C.M. × H.C.F. = 48 × 8 = 384
Product of numbers = 16 × 24 = 384
So, from the above explanations we conclude that the product of highest common factor (H.C.F.) and lowest common multiple (L.C.M.) of two numbers is equal to the product of two numbers
or, H.C.F. × L.C.M. = First number × Second number
or, L.C.M. = First Number×Second NumberH.C.F.
or, L.C.M. × H.C.F. = Product of two given numbers
or, L.C.M. = Product of Two Given NumbersH.C.F.
or, H.C.F. = Product of Two Given NumbersL.C.M.