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# Think i have it, but don't know what to do with reduce()

I've been working on this code challenge for some time now, but i'm stuck!

Here's my error (what i get when i run it in a general workspace):

error.txt
```Traceback (most recent call last):
File "Untitled.py", line 17, in <module>
print(list(total))
File "Untitled.py", line 13, in product_sales
return twomemtup[0] * twomemtup[1]
TypeError: 'float' object is not subscriptable
```

Here's my code:

prices.py
```from operator import add
from functools import reduce

prices = [
(6.99, 5),
(2.94, 15),
(156.99, 2),
(99.99, 4),
(1.82, 102)
]

def product_sales(twomemtup):
return twomemtup[0] * twomemtup[1]

total = map(product_sales, reduce(add, prices))
```

(in the variation on the workspace, i add:)

```print(list(total))
```

PS: the treehouse code challenge engine says:

``` Bummer! total isn't the right amount.
```

You nearly had it. You just need to map first, and then reduce:

```total = reduce(add, map(product_sales, prices))
```

You have map and reduce reversed. Since reduce reduces a collection into a single value, and you are trying to find a sales total from individual sales, it should be the outermost function.

```total = reduce(add, map(product_sales, prices))
```

Thanks! since both of you responded on the same day, i don't know who to give best answer!

I though i was doing it first!

man, i'm dumb!