James wants to build a 16-foot by 20-foot quilt.  He uses patches that are each 4 square feet.  The first 10 patches cost $10 each and then each patch after that cost half as much.  How much do the patches for the quilt cost? Let's think step by step and output the final answer after "####".
user
The patch is 16*20=<<16*20=320>>320 square feet
So he needs 320/4=<<320/4=80>>80 patches
The first 10 patches cost 10*10=$<<10*10=100>>100
He gets a discount on the next 80-10=<<80-10=70>>70 patches
They each cost 10/2=$<<10/2=5>>5
So in total they cost 70*5=$<<70*5=350>>350
That means in total he paid 100+350=$<<100+350=450>>450
#### 450
James wants to build a 16-foot by 20-foot quilt.  He uses patches that are each 4 square feet.  The first 10 patches cost $10 each and then each patch after that cost half as much.  How much do the patches for the quilt cost?
train