In English, but also in Math, 'Eleven plus two' Equals?

A: 'Let's go for a ride! I'm picking a horse.' B: 'Yes, I want a horse too!' A: 'Haha, you're behind me, now you'll never catch me!' B: 'So! Only because the horse next to you was already taken.'

I’m always around on a sunny day. Pan grew annoyed when I ran away. Cast over your face means you’re feeling dismayed. I need another line so hooray for croquet.

Floppy-eared bounder in the meadow, Though to find my true home, look down below. Bouncing through fields is never a bore-ah, Remove my last and I'll teach you the Torah.

I can be mined but never grown, I make you strong though I’m not bone. I bend with fire, break with rust, In me, your tools and blood both trust.