High School

(a) The H.C.F. and L.C.M. of any two numbers are 6 and 36 respectively. If one number is 18, find the other number.

(b) The H.C.F. and L.C.M. of 'x' and 210 are 30 and 2310 respectively. Find the value of x.

(c) If the H.C.F. of 45 and 60 is 15, find their L.C.M.

(d) The product of two numbers having H.C.F. 14 is 1260. Find their L.C.M.

(e) The product of two numbers is 448 and their L.C.M. is 112. Find their H.C.F.

Answer :

(a) To find the other number when the H.C.F. and L.C.M. are given, we use the formula:
[tex]\text{H.C.F.} \times \text{L.C.M.} = \text{Product of the two numbers}[/tex]
Given H.C.F. is 6 and L.C.M. is 36, one number is 18.

[tex]6 \times 36 = 18 \times x[/tex]

So, the other number, [tex]x[/tex], is
[tex]x = \frac{6 \times 36}{18} = 12[/tex]
Thus, the other number is 12.

(b) Given the H.C.F. of [tex]x[/tex] and 210 is 30, and their L.C.M. is 2310, use the same formula:
[tex]30 \times 2310 = x \times 210[/tex]
To find [tex]x[/tex]:
[tex]x = \frac{30 \times 2310}{210} = 330[/tex]
Thus, the value of [tex]x[/tex] is 330.

(c) Given the H.C.F. of 45 and 60 is 15, we use the formula:
[tex]\text{L.C.M.} = \frac{45 \times 60}{15}[/tex]
Calculating gives:
[tex]\text{L.C.M.} = 180[/tex]
So, their L.C.M. is 180.

(d) Given the H.C.F. is 14 and product of two numbers is 1260, use:
[tex]\text{L.C.M.} = \frac{\text{Product of the numbers}}{\text{H.C.F.}}[/tex]
[tex]\text{L.C.M.} = \frac{1260}{14} = 90[/tex]
So, their L.C.M. is 90.

(e) Given the product of two numbers is 448 and their L.C.M. is 112, we find the H.C.F. using:
[tex]\text{H.C.F.} = \frac{448}{112} = 4[/tex]
Thus, their H.C.F. is 4.