You're cheating again.
- Not explaining if a single axe would be considered a different symbol from double axe, or half the value. Any interpretion is possible.
- Systematically putting a multiplication at the end of the line, so nobody can know if you're intending to multiply first (as in maths) or adding first (as if the calculation should be made in order, two operands at a time).
This way, you can reward whoever you want by just picking either solution you want, not even knowing in advance which one it should be.
That's just dishonest.
If you're calculating on the go, then you get (30 + 50) x 5 = 400
But if you're caculating the normal way (but maybe not yours), then 30 + (50 x 5) = 280