This one is tricky - math riddle

[SquarePeg]

One guess only.

update
Petrochemist was the first to get the correct answer!

 

[dxqcanada]

3x=30 ... x=30/3 .. x=10
2y+x=20 ... 2y+10=20 ... 2y=20 -10 ... 2y=10 ... y=10/2 ... y=5
2z+y=13 ... 2z=13-5 ... 2z=8 ... z=8/2 ... z=4
x+y*z= ... 10+5*4= ... 10+20=30

 

[SquarePeg]

3x=30 ... x=30/3 .. x=10
2y+x=20 ... 2y+10=20 ... 2y=20 -10 ... 2y=10 ... y=10/2 ... y=5
2z+y=13 ... 2z=13-5 ... 2z=8 ... z=8/2 ... z=4
x+y*z= ... 10+5*4= ... 10+20=30

sorry that is incorrect

 

[limr]

15?

 

[johngpt]

14

 

[RowdyRay]

19

 

[Space Face]

19 is what I get too.

 

[vintagesnaps]

19...

 

[petrochemist]

Not difficult at all IMO, except we're tricked into thinking the last line is all additions (which would be 19)
@dxqcanada is correct, as multiplication is done before addition unless brackets are used.

 

[Space Face]

Ah, so 60 then. Well spotted.

 

[Original katomi]

17
Shoe 10
Boy 5
1 peg/scarf 2
Ok you got me, brackets? Whooosh as it goes right over my head lol added that I miss read question in the first place .da

 

[Space Face]

30

 

[weepete]

60

 

[Dean_Gretsch]

I also get 17.

 

[photoflyer]

19