Respuesta :

unknown54321
10 pencils. if he had 4 packs of pencils and each pack contained 10 pencils he would have 40 pencils (4x10) and if he gave 3/4ths of it away he would have one 4th left, so just divide 40 by 4 
apologiabiology
first find how many pencils he had total
packs times pencils per pack=total
4 times 10=40 pencils

gavve 3/4
so he has 4/4-3/4 or 1/4

1/4 of 40=1/4 times 40=40/4=20/2=10
he kept 10 pencils

another way is

4 packs
he gave 3/4 of that away and had 1/4
1/4 of 4 s 4/4=1
he had 1 pack which was 10