By working with percentages, we will see that they served 56 salmon filets.
Here we know that the restaurant served 70 specials in total, such that 80% of these were salmon filets.
So we just need to calculate what is the 80% of 70.
This is just given by:
70*(80%/100%) = 70*0.8 = 56
This means that they served 56 salmons filet.
If you want to learn more about percentages:
https://brainly.com/question/16148316
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