Question

find LCM and HCF OF....(1) 510 and 92 ,(2) 72 and 90, (3) 12,15, and 21 (4) 8,9 and 25​

Answer 1

Answer:

(1) 510= 510÷2=255÷5=85=17=17=1

92= 92÷2=46÷2=23÷23=1

LCM =

$2 ^{2} \times 3 \times 5 \times 17 \times 23 = 23460$

HCF=

$2 ^{2} = 2$

Step-by-step explanation:

(2)= 12= 12÷2=6÷2=3÷3=1

15=15÷3=5÷5=1

21=21÷3=7÷7=1

LCM=

$2 ^{2} \times 3 \times 5 \times 7$

$= 4 \times 3 \times 5 \times 7$

$= 420$

HCF=

$3 ^{1} = 2$

72 90= LCM=360

Answer 2

:

Mark Me As Brainliest And Thank Me If The Answer Is Useful.

-- :

Using prime factorisation method:

(i) 12, 15 and 21

Factor of 12=2×2×3

Factor of 15=3×5

Factor of 21=3×7

HCF (12,15,21)=3

LCM (12,15,21)=2×2×3×5×7=420

(ii) 17, 23 and 29

Factor of 17=1×17

Factor of 23=1×23

Factor of 29=1×29

HCF (17,23,29)=1

LCM (17,23,29)=1×17×23×29=11,339

(iii) 8, 9 and 25

Factor of 8=2×2×2×1

Factor of 9=3×3×1

Factor of 25=5×5×1

HCF (8,9,25)=1

LCM (8,9,25)=2×2×2×3×3×5×5=1,800