Question

Using prime factorisation method, find the hcf.(a)25 and 35 (b) 18 and 15 (c)16,32 and 48 (d) 10,25 and 30 (e)27, 63 and 54 (f)18, 30 and 27​

Answer 1

Answer- (a) 25 and 35.

25= 5x5

35= 5x7

so, H.C.F. = 5

(b) 18 and 52

18=2x3x3

52=2x2x13

so, H.C.F.=2

(c) 16,32 and 48

16=2x2x2x2

32=2x2x2x2x2

48=2x2x2x2x3

so,H.C.F.=2X2X2X2=16

(d) 10,25 and 30

10=2x5

25=5x5

30=2x3x5

so, H.C.F.=5

(e) 27,63 and 54

27=3x3x3

63=3x3x7

54=2x3x3x3

so, H.C.F.=3x3=9

(f) 18,30 and 27

18=2x3x3

30=2x3x5

27=3x3x3

so, H.C.F.=3