The girl wants her candle to be exactly 28 cubic cm. she wants the sides to be in whole cm.How many different miolds can she make?

Question

I tried it  multiple times but i could not get the answer but i think the closes answer is 3.

Answer 1

It is to be ASSUMED that the candle is a 'rectangular solid.'

 

Volume = LWH =28 cm³ and each dimension, L, W & H must be an integer.

 

Since the prime factorization of 28 is 2²(7),  and you must choose one of the numbers 1, 2, 4, 7, 14, or 28 for each dimension, AND IT'S OK TO CHOOSE  the number 1 more than once, you should try listing all distinct choices of three dimensions:

 

1,1,28   1, 2, 14   1, 4, 7   2, 2, 7.  That's four possibilities.  Can you see any more?