英文一問!!!!!!!!!!!!!!!!

小明有m個蛋糕,呀小有12個蛋糕,呀明有6個蛋糕,共有29個蛋糕:
29-(12+6)=個m。 m=11。
變成:
Young Ming has m cake,Slightly has 12 cakes,Clearly has 6 cakes,Altogether has 29 cakes: 29-(12+6)=個m。 m=11。

Let x be the number of cakes that Siu Ming has

or simply,

Let x be the number of cakes

let x be the the amount of cakes that siu ming has