The expression 20l+25g−10, gives the number of dollars that josie makes from mowing l lawns and raking g gardens. how many dollars does josie make from raking 4 gardens and mowing 3 lawns?

Josie makes $150 from raking 4 gardens and mowing 3 lawns.
 
Given:
Expression: 20l + 25g - 10
l = 3
g= 4

20(3) + 25(4) -10 
60 + 100 - 10
160 - 10 = 150

So,

20l + 25g - 10

"l" represents the number of lawns Josie mows, while "g" represents the number of gardens Josie rakes.  Substituting the given values into the expression, we get:

20(3) + 25(4) - 10

Simplify.
60 + 100 - 10
160 - 10
150

Josie makes $150 from raking 4 gardens and mowing 3 lawns.