This question can use LCM and HCF to find the answer
As the question ask for least number of xxx, then we should find out the LCM of 8 and 12.
2 | 8, 12
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2 | 4, 6
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2, 3
LCM = 2 x 2 x 2 x 3 = 24
1 pack of burger meat = 8 pcs, how many burger pack need to be purchase = 24/ 8 = 3 packs
1 pack of buns = 12 pcs, how many bun pack need to be purchase = 24/12 = 2 packs
Least number of burger meat to purchase: 3 pack
least number of buns to purchase : 2 pack