Answer :

s+g=316  "s"=strawberry "g"=grape
g=52+s

plug in for "g" to find "s"
s+(52+s)=316
2s+52=316
2s=316-52
2s=264
s=264/2
s=132

find "g" 
g=52+132
g=184
132 strawberry drinks and 284 grape drinks.