In the video “All Arithmetic Mega Practice” @1:04:04 (link:All Arithmetic - Mega Practice - GregMat), Greg says there’s a trick to solve that question. Can somebody help me find it?!
Thanks mate! 
In the video “All Arithmetic Mega Practice” @1:04:04 (link:All Arithmetic - Mega Practice - GregMat), Greg says there’s a trick to solve that question. Can somebody help me find it?!
Thanks mate! 
The video titled “factors and multiples” around the 16th minute mark
Thanks Vidisha! You’re awesome! 