Reversing the steps to obtain the amount she spent at the supermarket, $50 less than $350 is $350-$50 = $<<350-50=300>>300
If $300 was thrice the amount she spent at the supermarket, then the amount spent at the supermarket was $300/3 = $<<300/3=100>>100
In addition to what she spent fixing her auto, she spent $100+$350 = $<<100+350=450>>450 altogether
#### 450